What is the best eye drop to relieve tired eyes that I can use daily?

Lubricants. The only thing really safe for daily use would be an artificially tear. There are many many options. Try a few and choose your favorite. If using more than 4 times a day, consider a non preserved drop.
Artificial tears. The safest eye drop that you can use daily is lubricating artificial tears, which will help dry eyes. If preserved tears though, shouldn't use more than 4 times a day. Visine or any with a vasoconstrictor should avoid daily use due to risk of rebound redness on cessation. Best is to figure out why the eyes are tired. Refractive error? Not enough breaks?