1. 21/male, vaguely effeminate but hetero otherwise
2. When I have them, once every 7-10 days.
3. Every. Fucking. Day.
4. A few different methods. Method one is meant solely for relief of sexual tension. Usually done with some degree of stealth, I have done it anywhere from an office, to bathrooms at friends' houses, backseat of the car on car rides, a few risky situations. Method 2 is normal. Fap to whatever; diaper girls, messing girls, upskirts, vintage porn, etc. My normal fap, and most common. Method 3 was devoted to fapping solely to a waifu back when I was a ponyfag. It is obsolete as I no longer have a pony waifu. Method 4 is the most extensive. Usually begin preparing a day in advance; eating and drinking without going to the bathroom, and I make sure nobody will be around. I go to the main bathroom, give myself an enema, pad up (First I chose 24-7, then I went to ABU Space, going ABU Simple next time), and I mess and wet. Then sit in it in the bathtub and fap to messy diaper girls. This one is the strongest; I've nearly blacked out on numerous occasions.
5. It is my first and primary fetish. I have numerous, lesser fetishes, and can get off without any of them, but each one is like a… what video games call a "buff". With diapers being the strongest buff.