I may as well add my two cents worth...

I was taught to make my turn on to final 'late'. Turning on to final is a bit of an optical illusion. By turning late, you THINK that you are going to overshoot the field and come in too close, but you don't.

As noted above, once you have your turn where you want it, pick a spot (a tree, barn, etc) that will serve as a landmark for future turns.

Of course, make your first few turns at high altitude to make sure that your turn gives you the lineup that you want. You might want to do all this practice when there aren't many folks flying, just for your own peace of mind.

Hope this helps,

Bob