Well, some ppl mite have naturally clear skin but for ppl who dont heres a tutorial on airbrushin, (p.s this is my first tutorial

)
Get a picture of yourself, i used kanye west
Then desaturate it (optional)
Then Go 2 Filter/blur/gaussan blur, then set it 2 two (it differs with the size of the pic)
Then go to layer/layer mask/hide all
Then use a soft rounded brush around the skin
Then duplicate the original picture (without the airbrushing) then put it on gaussan blur 6 & layer mask again
Then use a rounded brush on most of the skin, try not to blur/overblur any vital parts e.g glasses, ears, eyes, mouth or eyebrows
Plz post outcomes