This is complex and maybe a little twisted, but it is good.
You'll need one the many new masturbation aids that are available for men. Hey, if it's OK for women to have 'devices'.....
You'll also need condoms, cock ring/s and a good water-based lube. Fantasy material of your own preference is also a given.
Of the lubes that are out on the market nowadays, I find most are a little sticky and thick. I am circumcised and prefer a little more friction than most offer. I get a quantity of lube and water it down a little, say 75% lube and 25% water. Stir it around with your finger and make sure it's well mixed.
Secondly, get the condom out of the packet and fold it down one turn. Then dry the prepackaged lube off the outside and inside of the condom down to the roll remaining.
Pour the diluted mixture of lube into the head of the condom and then force your erect penis down into the condom before rolling it onto your penis. The idea here is you end up with a condom that is well stuck on your penis, with a little bubble of lube hanging off the end of it. It should be enough rubber to allow the head of the condom to roll over the head of your penis a little.
Now get one (or two or more) cock rings and stretch them over the rubber down over your penis. At least one of them should be over the base of the condom, obviously to help hold it on. I use the rubber stretchy ones. You should now be able to safely slide the top of the condom up and down over the head (or more) of your penis, a very nice feeling. Don't get too carried away, we're not done yet.
Now get your masturbation aid and stick your fingers inside and stretch it wide so you can get your whole penis inside without lubing it up.
Using the aid you should be able to get a nice even sliding feeling over the whole top half (or more) of your penis.
Now the icing on the cake (no pun intended).
I then put the whole lot in a plastic 'freezer bag' for safety sake and (on my knees), slip it between the mattress and its base on the bed. Then I gently shag the bed to a delightful climax.
The benefits are many. The condom makes cleanup real easy (although it is fussy to set this one up). The diluted lube, condom and 'device' makes a wonderfully slippery and smooth combination. The bed makes the whole thing hands free and very 'fantastic'.
The cock rings do hold back a certain amount of semen and make it easier to cum again sooner.
I am currently experimenting with extra rings at the base of my cock to try and keep the bulk of semen from coming out. The less comes out, the more often you can cum, simple physics.
This is probably ideal for men who have been circumcised. Of course I had that done when I was just a nipper, so I can't comment otherwise ;-)
[Webmaster's note: Solo's position on the matter of holding back your cum, is that it could be dangerous. I suggest you try this technique without the rings.]