Kilroy Was Here (en.wikipedia.org)

The oldest extant meme I'm currently aware of is "follow me" sandals:

https://sarahemilybond.com/2014/10/06/follow-me-courtesan-sa...

https://www.etsy.com/listing/80717468/follow-me-bring-wine-f...

I first saw this meme as a spray decal in Half-Life Counter-Strike beta 0.7.

Tempus fugit

When I was a wee lad I used to draw/scribble this everywhere

I approve of this one.