30+ years ago when overlanding we put a load of stickers on our panniers before leaving, really just to decorate/break-up the vast areas of grey aluminium; once out of Europe we realised these were beginning to disappear as wherever we went the kids were 'stealing' them.
Sent a letter back to a friend in the UK who asked around the motorbike clubs/rallies (we all have a drawer somewhere with a few or more in don't we) and Dave collected and sent me a package of 100s of them out to India. Thereafter we gave quite a few away, but for the most part we continued to stick them on the panniers - being careful to always leave one edge unstuck, so they'd lift off without tearing - as the kids seemed to enjoy them more if they could 'steal' them off the bike.

For years I never put stickers up but I’ve started putting them on for really serious, far flung countries that I’m pretty pleased to have got to. These only go on the panniers though.

Two exceptions. In America I put a GB on the back as Yanks are very friendly and generally like Brits. And in Latin America, heading north, I put a Union Jack flag on the screen to say I’m a Brit. People saw it and were quite pleased and chatty as they generally assume all gringos are Yanks.

Love my stickers, and signatures from friends I’ve made along the way