A few words about Edinburgh in August…
The Edinburgh Fringe is the biggest arts festival in the world, and that’s only one of the festivals that run concurrently. There’s also the International Festival, with classical music and drama (note: this was the original one, and the Fringe grew as a sort of protest/add-on to this) and the Book Festival. Plus of course the Edinburgh Tattoo, which I know is very popular in this forum.
It’s very easy to see Fringe shows without buying advance tickets - in fact, you’ll be assailed on every street by performers and flyerers trying to encourage you to visit their show. Many are free (donation requested at the end). It’s a lot of fun but it’s also an absolute onslaught. Even walking down the street can take much longer than usual.
Edinburgh is incredibly busy during August and hotel & accommodation prices tend to be three times as much as they are at other times. It’s an experience like no other. For some people it’s the best month to visit Edinburgh. But if you’re not particularly interested in the festivals, or if you’re not prepared for them, it’s the worst time.
The fringe gets underway properly on 4th/5th August but performers are arriving now and accommodation prices are hitting the heights. However if you’re literally talking about going tomorrow, that’s too early for the events and craziness.
If you’ve already found accommodation, go for it - but do double-check the accommodation. Every year there are horror stories about people who’ve booked Airbnbs or similar and find that their booking has been cancelled or rebooked to someone else for more money - that’s how crazy it can be.
However, it can be possible to find a hotel or hostel room for a few days.