I personally use emloop. It's what pikatimer was based off of from what I can tell, but it's all in japanese. It's easier for me to use a delay that's a little higher than normal, so I don't have to worry about button mashing and hoping I hit it right. I just simply watch the timer, keeping a rhythm in my head and and hitting A to enter the game when the last timer runs out. I'm usually within +/- 2 from my delay, at most +/-4.