It's hard work, looked into it a while back as bargains can be had, i'd pay to get someone to do it, hence why new era and the rest of them charge you handsomely for the pleasure.
You got to find it,
Get it to the point of export,
Get it De registered in the country of origin, and ready for importation into UK. Not sure how strict our laws are about seeds grass mud etc still being on or in the car
Find someone willing to ship it, a RORO cargo vessel i far cheaper but then you risk the people loading/unloading nicking bits, container would be best.
PAY for above shipping, insurance dock fees etc.
Wait six to eight weeks and hope it's not been hijacked by pirates,
Get it off the boat in UK, pay for storage, import tax, vat prepped for an sva if needed buy model report I'd needed prep for UK, fogs mph/kmh etc.
Sva test and mot. Probably pay more tax along the line.