Monikers is based on a public domain game, so there are lots of different ways to play:
If you're out somewhere, you can just pull cards from the box and try to get your friends to guess using the rules for Round 1 or 2. Probably no need to use a timer or keep score.
You can add rounds with different rules. We've seen people play rounds with making a single sound, holding a facial expression, and playing the charades round under a sheet. Seriously.
If your group is getting too big, you might want to divide into more than 2 teams. But if you do, still try to keep the total number of cards in the deck around 50.
If you're with a small group (4 or less), try playing cooperatively. Our friend Alan Gerding invented a fun variant where you set a timer-add 1 minute per card in the deck-and try to ﬁnish all 3 rounds in the allotted time (including reshuffling, etc).