Choose one of the ready-made games. You can pick from bingo with numbers or letters in various variants. For each variant, bingo cards are available for download. Print the cards, cut them into smaller pieces to have one bingo card per participant or team. When the game can start, you can use the shuffle button of the Letter or Number generator to pick a random letter/number call it out. Place the green tokens over the letters/numbers that have been picked to keep track of the game (or don't if you want to make the game a bit harder).