David Willis

Warm it up, peel it off, polish the car using a good quality general car polish.

Ask a good specialist sticker printer who may offer to sell some material to you for a few pounds.

Peel the decal from it's backing sheet. Line up where you want it to go, and gently rub it onto the wall. Remove the carrier sheet.

Not easy unless you have experience. Ask a local sign maker for a quotation.

Paying a vinyl installator to remove vinyl stickers from your car could become expensive if there are many of them and he charges by the hour.