Probably my favorite method is putting on any diaper, (usually a home-made from a garbage bag, taped around the legs and filled with napkins) walking around in it for a while, and drinking several glasses of water. Then, I sit down and wait for the urge to start. As soon as it does,i just kinda sit back and wet my diaper. It feels great just feeling the warm pee absorb into the diaper, and the damp, moist padding around my skin.
Then, when I'm finished with wetting, the fun begins. I start by feeling myself up, rubbing the outside of the diaper, and squeezing the wet parts through the plastic. While I'm doing this, I watch videos and look at photos of girls wetting and masturbating. After a minute or two of this, I reach my hand down into my diaper and start using whatever pee hasn't been absorbed to lube up my cock and i start jerking off. Then, I edge myself once or twice before taking my hand out and rubbing or grabbing my nipples. Once I've exhausted nipple stimulation, I either put a pillow between my legs and hump it like crazy, or start reaching around back and spanking myself (or, i decided to fill my diaper with oatmeal, squeezing that in and feeling it move around my ass). Then, I do what always makes me cum: putting my hand underneath, feeling the diaper all wet and soaked, and squeezing it while holding it right up to my balls - then I rub it up and down my using my free hand to keep jacking off, edging and edging myself until I can't take it anymore and cum sticky loads all over my wet diaper. Usually I feel kind of ashamed afterwards, but more recently I keep the diaper on if I'm alone, and sometimes even keep the wet, sticky cum-saturated diaper on till late night, when I rub another one out and have an awesome sleep in my completely ruined diaper.