I agree with all that has been said about getting proper instruction, and it truely will save you lots of headaches. I started with an instructor, but after issues with finding time for lessons, 6 months later I bought a GP Yard Stick and went at it alone. I had taken off with my instructor, but had only done a few landing aproaches and was a lesson or two away from soloing. With the Yard Stick I took off, flight trimmed, flew a few times thru the pattern and then lined up with the runway and landed for the first time. I am sure if I had not taken the initial time with an instructor, my going at it alone would not have gone so well.

The one thing I don't agree with is the fear of doing your own maiden flight after you first or second plane. The only plane I have not maidened was my first, and with that I was taught propper set up and mechanics by my instructor. The only way to learn flight trimming is to do it... Is it scary sometimes? Of course! But I have not lost a plane doing so and have learned many lessons doing it myself. I don't suggest doing this until you have mastered the basics of flight, including deadsticks and a few self inflicted out of trim issues with your trainer. So long as your second plane is not past your skill level (ie: going from your trainer to a 3D type, Warbird, or Pattern plane) trimming should be no problem and it is better to learn on an easier to fly plane than one that is more advanced for sure. Why put it off?