Relaxing when playing

Hello all,
Like some advice
Relaxing when playing I seem to all of a sudden become tense my left arm and fingers become so tense that I find it quite hard to move to move to another note when practising. I do breathe when playing as it stops cramp in the muscles in the body

Was hoping that someone can tell me any tips that can help me to relax when practising?

Any help most welcome even links

many thanks

im still new at guitar but maybe your action/string height on your guitar is higher than usual?

Well, before you start playing just take a few deep breaths and keep breathing regularly while you play. Its essential to keep loose!

You might wanna dig up a video of Marty Friedman playing watch him when he hits a real spine-tingling note, he emphasizes it but he doesn't tense up.

one thing you might try to relax besides simply breathing is stretching. extend your hand out with your elbow locked as if you are signaling to stop... (or you're telling someone to talk to the hand, haha). keep your fingers straight up, and bend them back towards you slowly while taking nice, slow even breaths. that will help relax your mind and also help to keep your hands nice and loose, while at the same time, preventing you from injuring yourself. hope that was of some help... if you're not quite sure what i meant, i'll try to link you to a picture of the stretching exercise