Exactly the same as any other country.
You look up postal rates, Royal Mail our prices, or get booklet from Post Office, wrap up as for UK, put on an airmail sticker and Customers Declaration. Form CN 22 available at Post Office who should be able to advise on completing it. It is very simple.
Buy postage at Post Office, using a tracked service especially if over £20 in value. That will ensure thst you are paying the correct postage, DO NOT take any notice of ebay guesses at postage costs.
