Storm1974
Junior Guinea Pig
If you can wait, wait ideally until they come out and take food from you. Hold any hair losely from the body before you start brushing/disentangling from the hair tips so you are pulling as little as possible.
Personally, I let the hair grow long for one 'glam model' picture but otherwise keep it shorter to allow them a happy active piggy life without hair getting underfoot and plenty of matting. But each long-haired piggy is different and you have to 'learn' them and their quirks.
Love the idea of a 'glam model' picture!

Leo (the long haired one) has already taken a little bit of food from me, so it looks like he is going to be the tamer one.