Buy the cheapest FMJ ammo you can get for practice, and any name brand JHP's for self defense. XD's eat anything, as a rule.
Most of the practice ammo you find is 115 grain, in 9mm. If your gun shoots consistently low (like 6" at 7-10 yards) with 115's, you may want to order some 124 grain FMJ's for practice. The heavier bullet stays in the barrel longer, therefore the point of impact will be higher, because the muzzle will have risen a little more before the bullet leaves it.
You always need to see what your particular handgun 'likes' the best. I have had two 9mm's that shot to POA with 124 grain ammo and were always low with 115's. Most shoot OK with 115's, but not all. You should be shooting well enough after a couple hundred rounds to judge whether you need to try a different weight bullet.
I clean my XD45 by removing the slide and disassembling it (not hard), spraying it with Breakfree CLP (available from Walmart) and brush it and the inside of the frame with a nylon brush. Wipe clean with an old tee shirt and Q-tips. Dip a copper bore brush in Hoppes solvent, and run it through the barrel a few times, then run clean white patches through, till one comes out clean.
I usually put a single tiny drop of oil on each of the slide rails, and let it run down the length of it, before replacing the slide. It's not really necessary because the CLP lubricates everything fine, but it's an old habit, and doesn't hurt anything.