Oktoberfest

Entrance to Oktoberfest is free. Beer, food, and rides are a different matter. Sit at any table with open seats. All the tents are fun in my experience.

Our experience was that many of the tables are only reserved for groups (like corporate parties) for part of the day, usually evening. Just look for an area where there're active servers. The fun is not organized, just a band and/or drunken singing going on, so you bring the fun. And no futzing around - its a Mas of bier, no small glasses allowed.

Outside the tents is a giant carnival. like the largest state fair you've ever seen.. During the daytime, the crowds are multi-generational families walking about the fairgrounds eating and doing rides, so its not just about beer.

The larger the party the harder it is to get seats together. This is amplified later in the day/evening.

If I had a group of more than 4, I’d probably pre-purchase seats/tickets where available

4 seems like it could typically be done just squishing in, 2 people we could almost always find a seat in most tents.

If you go in the evening, or on a weekend, it can be tough to get a seat at a table. You must be seated to get a beer, a few tents though do have stand up tables. Even if crowded, you can usually at least get into a tent to look around

I usually go on a weekday afternoon and have plenty of choices of tents, grabbing a beer in several. As for best tent, there is some information on line that talks about the character of each tent, but for me, I listen to the band for a while, if they are a party band, playing a mix of classics and modern songs, then that is where I go. The traditional bands are fine, but more fun is had when the crowd gets into it.

If you are set on getting a seat on a busy night, you could look for a "tour" which usually includes a walking tour, some history, and a seat at a table. The other option is to make a reservation, that is done by reserving a table for 10, and prepaying for food and drink, something like 350-400 euro these days. If you are only a couple, it can worth a try to wander the tents and ask servers about open seats, or chat up a half filled table to see if there is room.

Is this for Greece??

If you go during the first part of the afternoon, you can enjoy everything without the crowds or the hassle of getting tickets for a table.