This is just my own thoughts and instructions, please feel free to add more info.

Things you will need: Slightly bigger than your own cock, dildo or vibrator, and plenty of lube :)

My cock is seven and a half inches(gotta add that half inch, lol) I'm not sure what length you will need, but anything close will do. This is the pre Self Ass Fuck stage. Try stretching your flaccid(soft) cock to your asshole. If you can't reach, Self Ass Fuck might not work for you. Now, get yourself good and horny, make that cock hard as it gets. I recomend fucking your ass with a dildo slightly bigger than your own cock to loosen up. It might also help to get into your most comfortable masturbation area or position, for instance, quiet room, lying down(whatever works for you)... I jerk it to tranny porn for this step:) This is to help achieve making the cock longer or bigger. Just get turned on to your fullest, loosen up and clean that tight ass!

Second stage: Now you have to let that cock chill. Let it calm down. This might be a good time to pull that fake cock(dildo)out. It's gonna be tricky with all that lube around, that's why you should only lube the asshole. As your cock starts to get soft, pull or push it towards the asshole. Notice the cock will flip or be sideways. It should not hurt... If it does, let it get softer. The only pain I get is in the pubic area due to the pushing, it's like razor burn, but goes away whitin hours. Push and hold the base of your cock with one hand, while pulling the tip(cock head) towards the hole with the other hand. Once you get it in, try moving to different positions for comfortability. It's kind of hard to do with a half soft cock, but don't get angry. I failed many times and lost hope... Look at me now :)

It might not work as good as you think the first few times, but you'll learn.
GOOD LUCK!!

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