I tend to have a few beers before I play they usually settle any nerves.
I tend not to get overly nervous when I am playing my local nights nowadays. However when I made my London debut I was bricking it a bit but I just tried to tell myself it was no different to any other gig, and I was right once I got going the nerves dissapeared.
I have also come to realize that everyone is there to party and won’t notice the minor errors that you will notice.
When I play out there are generally only two of my mates that will notice them. One of them used to live with me and the other is at my house alot so have heard me mixing hundreds of times and will happly critisise everything I do and tell me when something is shit(What are best mates for eh).
People will only notice mistakes when they are big clangers. But it is good to have experienced them as well as you learn more from your mistakes than anything else and it will stand you in good stead for the future.
I’m usally quite happy and nerve free once I have the first mix nailed and out of the way.