From James Kerwin’s advice (admittedly the 10k → 1k section):
… you should know that the rate at which you can hope to improve depends on the difference in strength between you and your common opponents. You can improve quite rapidly when you are playing much stronger players. If you are mostly playing players of about your own rank or weaker players your improvement will be very, very slow. …
But in your efforts to get games with stronger players, I encourage you not to neglect playing weaker players too. These games can be very useful in learning how to apply go theory. Stronger players will resist your strategies making it hard to implement them. Handicap opponents offer less resistance, and it’s easier to see how a strategy is supposed to work. In addition, if no one played weaker players no stronger player would play you either, and then where would you be?