It's In The Bag
A technique I've used for years is as simple as a routine drug store purchase: a tubular shaped ice bag. I take a lubricant, such as aloe vera gel, and slather it on my dick. Then I invert the ice bfor a snug fit, then go to town. No muss, no fuss. Just place it under the faucet when finished, and rinse, then re-invert it and let dry. Being tubular, and often of ribbed texture, it can reproduce the feel of the vagina, if copiously lubricated.