Hello ! We have a lot of experience, both of him solo, and of her stimulating him :)
If you have to take away only one thing from this rather long post, this is the one : TAKE YOUR TIME ! Anal pleasure is learned and earned, not available from the get go like penile stimulation.
Now, for some details ! You have to learn how to feel good through there. Touch yourself, feel the anus, at first externally only, always using more than enough lube. Lightly press on the hole, feel the muscles responding, feel the tightness come and go with your breath... You must be relaxed, truly relaxed in mind and body for it to work. After some time, some days of this, when you feel truly comfortable, you may want to push this finger inside.
Hygiene wise, see what you're comfortable with. We don't necessarily recommended enemas, just going to the toilet and pushing good to empty your bowels should work fine if you have a balanced diet. A soapy finger on the exterior of the anus and the first few centimeters, and you should be alright. But, the ass is the ass, and no matter what you do, there is always the risk of some crap being here. Just deal with it, it's nothing bad, when it happens, just clean yourself or the toy, and keep playing :).
So when you finally work a finger inside, go slow, just a few centimeters at first, always very lubed. Don't necessarily move, just feel it, the space it takes, how your sphincters want to react. Again take the time to process it. At no point in any part of the process should it hurt, even slightly. You may feel a slight discomfort, because these nerves are not used to stimulation, but absolutely no pain at all ! If there is some pain, stop immediately before you injure yourself, and go back so steps to relax and learn.
When you have "accepted" the finger, you can try to move it a bit, with two goals. First, stimulate the anus itself, and learn the sensations it can give. Second, finger arched towards your belly, to try and feel your prostate. You probably won't feel anything special, or barely so, when you first touch it, only something a bit hard to the touch, about the size of a nut, on the upper wall a few centimeters deep. BE VERY CAREFUL AND GENTLE, touch it slowly, lube and more lube. You will perhaps start to develop some nice feeling after a while, perhaps after a few times.
At this stage, you have several options depending on preference. You may want to keep going with the finger, perhaps fingerS (always slow and careful with progression !), or start exploring toys. Again, a matter or personal preference, we would not encourage vibration toys at first. A nice and simple prostatic stimulator will allow you fine control and progressive discovery of the sensation it can give you. You can also stimulate your sex when playing in your ass, but be aware this can easily drown all the more subtle feelings from anal stimulation, so we wouldn't really advise to.
Play like this regularly, and it should feel better and better, until perhaps, in a time of great relaxation and connection with your body, you will reach an anal orgasm :) It may come with some ejaculation, it may not. It may be body shaking, it may be subtle and prolonged... But it will be amazing :)
And when you're experienced enough, then try new things, new toys, perhaps some vibrating ones now that your prostate is "educated" to its one pleasure, perhaps mixing with genital stimulation... The options are endless :)
We hope this wasn't to long or confused, and we hope to have answered well enough ! Please don't hesitate to ask us further questions if you want to :)
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