Don’t dress up pretending to be a witch, fairy godmother and so on as it will only antagonize the real witches, fairy godmothers and so on. Fancy dress is something the Kingdom finds strange. The magical groups prefer people to be what they are and dress accordingly.
Find out who the authorities are and keep your head down. Locally, find out as quickly as possible who runs the village (someone always does) and live a quiet life. Alternatively make your magical powers so magnificent it is you who runs the village and nobody argues with you. (Not a long life guarantee that one as someone always covets power and position).
Study and take in any information from the wonderful Rough Guide to Fantasyland so thoughtfully provided by the late Diana Wynne Jones. It applies to all fantasy worlds.
Always be wary of old swords, strangely golden rings with funny writing on them and anything that looks as if it might belong to an evil wizard of long lost king. You don’t want to get involved with any of that nonsense. It always means certain death for someone. The clever bit is ensuring that someone is not you.
Also if you come across a police box where you wouldn’t expect to find one, give that a wide berth too unless you want your life turned upside down and threatened on a weekly basis.
Make yourself useful in whichever village you end up in as nobody wants to get rid of beings like that. The person who puts the rubbish out is less likely to be a target for killing than members of Her Majesty’s Council. Humility, a good manner and hard work go a long way here. They extend life expectancy too.
Always have a decent spell book on you (appropriate for your species of course as a sprite carrying a witch book can expect a nasty and sudden death if a real witch catches him doing so) and have emergency spells stored in your memory and wand so you can use them quickly. Speed is vital here. As in Earth’s Wild West you do have to be quick on the draw.