First, make sure your computer has the latest models of Flash Player and Shockwave Player to three games. Normally, Flash Player is loaded with automatic updates your computer, but if not, then download and install it yourself, it will take quite a bit of time.
Then you simply type in a search engine the phrase "flash games" and go to one of the many sites. Most sites with flash games free of charge and does not require you to send sms for the use of the game. Registration on the site is optional, but it will allow you to keep score points and send the results to your game friends. You do not have to download the game and install it on your computer, you will be playing online.
Now you need to choose a flash game from a variety of games on the site. Usually all games are grouped by category in the category "sports", "role", "quest", "race", etc. Each site has a description of all the games, driving instructions, and if you still have problems, in comments to a game you will be able to ask the site administrator or to other players. Just choose what you are interested in, turn on and enjoy a pleasant holiday for the flash game.