Take rejection with good grace! Don't take it personally, and be professional about it. It's about the work, not you.
Your artwork/craftwork may be fantastic - it may simply not fit in with the 'style' of the gallery.
Don't think a rejection is forever! It doesn't mean you can't go back a year later, with a new body of work.
Karen was really helpful about practical things like;
Contracts; they are there to protect you, as well as the gallery. They can be changed, if there are things you disagree with. Negotiate these with the gallery.
Delivery Notes; include clear and concise information. Include your name, and your trading name if different. A description of the work - if it's framed, unframed, textiles, ceramics, etc.
One delivery note can include all the pieces you're delivering to the gallery.
Don't harrass the gallery. BUT DO follow up on your initial contact.
This is quite a tricky one, as what one gallery considers to be 'harrassment', another will regard as being 'following up'!