I am relatively well informed about the import duties and VAT payable.

I believe I have all the information that I need to import , what forms do I need to send to the Revenue and Customs Organisation? How would I pay them for the import and VAT, if not billed by the courier?

Seems u wanna complete the customs formalities urself

Freind if u aint done this before then leave this territory for the pros known as customs brokers who are also at times freight forwarders.

Coz if u wanna bring stuff in by air or sea freight then u gonna have to venture into unknown territory and u may mess things up if things aint done by the book.

also how mush does ur shipment weigh coz and whats it worth? coz maybe ur better off using express courier like TNT, DHL, EMS, UPS, FedEx. in my experience if weight is less than 50kg it better to use express.