Going to a game
First, find an airsoft site to go to. There are many excellent directories out there, which can easily be found from a quick Google search.
Next, book yourself in, usually by emailing the game organiser from their website.
It is highly recommended that you drag a friend or two along to split fuel costs (you might get lucky and your friend might get into airsoft as well). Don’t worry about bringing a big group of people like you often have to with paintball, in airsoft you will always team up with other players on site. If your group doesn’t have access to a car, then unfortunately it may be difficult to play airsoft long term as airsoft sites are usually in the middle of nowhere.