pay for it and get company you buy it off to sort shipping their end.

IMO best to get a clearance company sort out what fees etc etc you owe and get it through customs, will only cost you about 60quid extra.

pay the duty etc and possibly shipping fees this end.

get the import/1st regsistration papers from the DVLA, fill em in, get it registered.

if its anything like cars though anything less than 10yrs old will need to go through an ESVA to be legal here, and that usually isnt cheap or easy.

ive just done all this with my car, but it was over 10yrs old so the SVA shite i didnt have to worry about.