For US and Canadian ops, The ARRL CW Sweepstakes contest starts Nov 7th at 2100Z - full rules and info
here.
If you are a casual operator, Sunday afternoon is always a good time to get on and be "fresh meat." You can only work a station once the entire contest, so by Sunday afternoon the full time entrants are combing the bands looking for anyone to work - great time to call CQ SS!
Sweepstakes has one of the more complicated exchanges of any contest, including a serial number, so a good contest for increasing your code speed. The
info page walks you through it but you will need to know what ARRL section you are in and what year you were licensed.
73 John K3TN