I suggest you contact a charter company and ask for guidance. They will tell you if you need more experience or training. I recommend http://www.fairviewsailing.co.uk/ . Another site that may be of interest is www.seanine.co.uk
...for details of the 'coding' required for your boat to be chartered. Or your selected charter management company, if you don't want to handle the commercial side yourself.
I would recommend my charter manager. It isn't a huge firm but effective advertising and lots of charters on the boats he does have.
He took care of all the coding for me and keeps the yachts in as good a condition as if they were privately owned (very unusual in my previous experience as a charterer)