If you are detail oriented and you want your cardboard project to look it's absolute best when completed you need to know this tip. And you need to know it before you start making the project!

Glue and adhesives take paint differently than cardboard. So.... when you are assembling your project try to be careful with the glues. Hide it as much as possible. Try to be neat with it. I ran a quick experiment for you to see.

I glued some cardboard together using three different adhesives; hot glue, elmers glue and 3 in 1 glue.

And I primed it with white paint.

After it dried I painted it all orange.

You can see that the various adhesives show up pretty easily. You probably won't have globs of it on your cardboard but it does show up too on the edges where two pieces of cardboard meet.

So, if you want to keep your projects super clean looking try to hide the glues and adhesives as much as possible.