When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Simple, replace the entire trunk with one without a sticker. Paint to match the rest of the car, if necessary.
If you're dead set on keeping the trunk that you have, you could use a very thin coat of bondo to cover the sticker and sand it down very nicely so it's smooth. Then repaint the area. If you want I can post a DIY. You can do the same thing with emblems, but you have to really make the bondo area big so it gradually bulges out and doesn't show as bad.
Also, if you car is white you can use liquid paper or if it's black a sharpie works pretty good. Not as good as liquid paper on white though.