Then, deliver your polished proposal. Save it in a PDF file or print it out, or both. The best delivery method for you depends on your relationship with the party who will receive your proposal. It's common to attach PDF files to email these days, but for your situation, it might be most impressive to hand_deliver a nicely printed and signed proposal.
Before you read anything else, the first thing that you need to understand is that proposals can be a huge waste of time for you and for your prospect. If they are not created the right way, and if the proper foundation hasn't been built, then you'll be spinning your wheels. Most proposals have a 25% win rate. If done right, your rate should jump to 60% _ 80%.