The MAFT is plug-and-play, but you have to also have some sort of monitoring device to see what your fuel trims are.
You can get a pda and free software (MMCd if you have a 1G and Tunerstein if 2G). I use MMCd and it is awesome. You can also get the Scanmaster 3 from fullthrottlespeed and that will work the same as the pda.
I got my Palm m125 from ebay for $25 and my cable for $15 from ebay (don't forget that you need a serial cable that will run about $14-19). I also bought the Scanmaster 3 and I use that most of the time now to monitor the basics.
Once you have a way of monitoring your ECU, then you can begin to tune.
Basically, set the AUX and BASE to whatever size injectors you have. Turn the IDLE knob about 2 or 3 clicks rich to start with. Then, take the car out on the highway and drive about 55-70 mph and watch your 02 trim (hold your foot as steady as possible--you want this trim to be as close to 100% as possible [0% if 2G]) and that will give you your base setup.
Once you have your base set up, you can start doing some pulls and adjust the MID and WOT knobs. Make sure you have a good base tune before you do this.
This should get you started and running well.
I hope this helps.