Here's a link to the manual:
http://www.paascheairbrush.com/parts_2003/HHSAirbrushPartsList.pdf
Cleaning a Paasche H is simple. There's three main parts that typically need to ble cleaned . 1) nozzle - the cone shaped thing you turn to adjust the paint output 2) needle - which the nozzle screws onto and is held into the ab body by an allen head set screw and 3) aircap - the thing that screws into the body of the ab and has the orifice where the air actually comes out. Often times, you only need to clean the nozzle and needle, as the aircap doesn't get fouled with paint very quickly.
Back off the set screw a turn or two (if you go further, you risk it dropping to the floor and it's hard to find because it's so small). Unscrew the nozzle all the way and use it to push the needle out of the airbrush. Clean with thinner (I use WW fluid because I only shoot water based acrylics) . Cotton swaps and/or pipe cleaners can be used (careful with pipe cleaners so the metal core doesn't damage anything). Compressed air can be helpful too, but it's not necessary. If the aircap is dirty (mine's only been so once in my last several painting sessions), unscrew it and clean it, too.
Reassemble, making sure the needle shoulder is fully seated into the airbrush. That's it!