–Well, the EASIEST clothes to put on him would be to color the body itself as if it WERE clothes. It already has the look of the less-than-well-appreciated form-suggesting spandex/kevlar armor featured in several superhero movies. You would then look in Insignia Tech for basic shapes to cover such details as you don’t want and downsize the hands, feet, and head a few percent. I usually type them in for a change below five percent.
More ordinary clothes would be started with multiple maskings, very good tutorials for which are listed throughout this thread and the ‘how do I’ thread. You would probably have to finish them with the same basic shapes or, as you get more skilled and familiar with the program, more innovative choices.
The same masking techniques are described well early in the custom pose threads, for example.
Good luck.