Recommended first day activities in London to keep my mind off jet lag?

Have you tried noise-cancelling headphones on the plane? I think the thing that most prevents me from sleeping on planes is people's conversations. Sitting next to window, sleep mask and not waiting to try to sleep until dinner is served may also help.

Our favorite arrival day activity in London is tea-really quiet and relaxing at Fortnum and Mason.

If by some miracle you can get into your room by 1 or 2, you could take a nap while the men do something(maybe Imperial War Museum) then meet them somewhere.

You will need to check on this, but an older version of Rick Steve's London book says British Library is open late on Tuesdays.

My first day in London had me on the street by 2 pm and as I was staying in Kensington on Gloucester Rd I walked a few blocks over and toured the V&A, had a snack, then walked further down and checked out Harrod's where I bought some goodies for dinner, and walked back to the hotel by 6 or so, stopping in a book shop. Out like a light by 8. Anything that gets you out and walking is great, for me I can combine that with touring one museum before I hit the wall.

Like you, I am not great at sleeping on planes. I have done the noise cancelling ear buds, the eye mask, the comfy clothes etc.. no dice

The key for me is to keep moving, preferably outside, and get on the local time as soon as possible as it relates to meals. Then hit the hay at 8 or so and start fresh the next day. I just did this when we landed in London and July 1 and it worked pretty well

Great advice here. I loved Skygarden.

Consider also taking a London Walks tour on your arrival day.

No prebooking, just show up, GBP 10 per adult and children under 15 go free if accompanied by parent(s).
I've taken 4 of their outdoor walks and all have been enjoyable.

It's my usual arrival-day activity because it gets me outside in the fresh air and I figure I'm less likely to fall asleep standing up. Plus, the guides are usually very engaging (many have theatrical training) and informative.
Here's the link to their Monday walks: http://www.walks.com/our-walks/monday-walks

Of the Monday walks, the ones starting off from Monument tube station or St Paul's tube station would be relatively near Skygarden, making it easy to do both activities.

I hope this time though you can rest on your flight. Have a great visit!

These are great ideas! The Sky Garden has no availability at all during our trip, but I will definitely add it to things to do on our next trip, as it looks fantastic and I hadn't heard of it before.
We already had London Walks on our list of things to do, but I hadn't considered going on one on the morning we arrive. That might be exactly the advice I was looking for! We actually get in on Tuesday, but many of those morning and afternoon walks look really good.
I will definitely be asleep fairly early at night- though I do tend to try and go as late as possible, simply to avoid waking up at 2 or 3am (another thing that happened in Ireland).
Thanks so much for all of the ideas. Keep 'em coming, if you think of anything else. Let's face it, I'll probably be awake and reading this forum right up until I land at Heathrow.

Recommend:
1. Staying outside (unless it's raining) to speed acclimation to new time zone.

2. Unstructured walk around the Mall down to Trafalgar Square then up Whitehall towards Parliament/Big Ben. When you get tired, you can hop on the tube back to your hotel.

Actually sounds like you are staying in Holland Park. As noted best to stay outside so here's my suggestion(s). Portobello Road market or Bike riding in Hyde Park or just walking through it or walking along Little Venice canals up to Camden Lock Market. London Walks as others have suggested.

No specific recommendations, but best advice is to stay outside (if weather permits) and walk, either an organized walking tour, a do-it-yourself walking tour, pick a park or neighborhood and walk around. No museums, cathedrals, stately homes, etc. - unless of course the weather is dismal.

Have you considered a movie right after dinner? We travel over to London every 8 months or so and after much trial and error have found a 'system' that works best for us. As a result of our flights we always seem to arrive at our hotel before noon and drop off our luggage. We then head on out, seeing some sight or another, not sitting down until an early dinner. Afterwards we catch a movie returning to our room by 10, and are able to sleep for a solid 6-8 hours. That next day we are good to go until evening.

We found the hop on hop off bus tour helpful. It gave us an overview of the key sites and a "street view" of London which you miss later traveling by tube.

Another vote for London Walks.

We landed at Heathrow at about 11am so about 6am our time after taking the red-eye. We arrived at our flat in Earl's Court at about 1 so we took showers and took a very brief rest before heading out at about 2:00. Our first stop was for lunch, so we had fish and chips and cider then went out to explore. We started off at Hyde Park just riding our bikes around and taking in the beautiful sites. After about an hour and a half of doing that we docked our bikes (loved using the Santander bikes) and headed towards Trafalgar Square. We explored the area a bit, walked down towards Big Ben and the Parliament building, walked across to the other side of the Thames to get a great view of Parliament and Big Ben, then walked back across and took the tube from Westminster station to Earls Court.

We were back in the flat by about 8 to get a good nights rest. In my opinion this type of plan works really well because you are outside the entire time and you are active. Being active will keep you awake while at the same time wearing you out so that when it comes time to sleep you are ready for bed and not stuck on your home time zone sleep schedule!

These are all great ideas. I'm hoping the weather cooperates so we can get outside. We are diamond members with our hotel, so if the rooms are available, we should be able to check in super early. If not, we'll be straight from the plane to the streets by 11 or 12. Leaning toward the 2 o'clock London Walks (whichever one we choose), as that gives us some time to grab lunch and meet our neighborhood for a bit. I had considered Portobello Market, though I don't know if my guys are onboard. May walk to the palace or Trafalgar. There is always Westfield if it's raining...but I'm not a big shopper, so that's a last resort idea.
Any experience or opinions on the available London Walks?
- "Somewhere Else" London
- Literary London
- Classic Westminster
- Plague, Fire, Hellfire
- Past the Palace

Tiffany-I have not taken any of the walks you listed below but you might be able to find more info in the reviews of London Walks on TripAdvisor. (Edited to remove my original advice to search TA reviews by the specific tour name in quotes--that doesn't work)

Alternatively, the folks who answer the phone at London Walks are very helpful and if you are trying to choose between tours they'll be able to tell you more about each.

I've done the Classic Westminster walk, it was excellent. I've had great success with London Walks and I'd take any of them, regardless of the theme of the walk.

I think I have done Classic Westminster. When I am fresh off the plane, I usually let proximity to where I am staying influence my choice. I like to minimize the agitation of that day so would probably not opt for a tour the other end of town from where I am.

I have not been on their site for perhaps a year. Looks like several fresh tours. Enjoy!

I know it is too late for this trip, but if you catch a 7:30am flight from the USA, you will arrive at 7:30pm London time then by the time you get to your hotel a couple hours later, it's time for bed & you'll wake up refreshed the next morning. This is how we usually fly & we avoid jet lag.

I suggest after dropping off the luggage go to the Imperial War Museum at Lambeth North, free entrance and the newly expanded museum and shops (since 2014) are great, bigger cafeteria, very, very nice. I don't get jet-lagged, since I sleep on the flight over SFO to London. My rule is never take anything, any OTM to induce sleep.