Okay, with a flybar, you can use some trim. But as Lee stated, make sure your swash is perfectly level by using either a zip tie or a swash leveling tool. Once that is done, and if it still has a drift (like Lee stated, a left drift on take off is completely normal, but above 3' is where you want to check) then use the trim tabs to level it out. Once you have it level, land it and look at your swash and servos. There shouldn't be an excessive amount of travel at mid stick and 0º pitch.