I find used tea bags work a treat! Take a couple of recently used cold ordinary tea bags, and lay back and relax for 10-20 minutes, or however long you need.
My eyes tire easily as I spend a lot of time on my computer and alternate between contact lenses or glasses.
And because I like to look after my health naturally, I was taught as a child by my grandmother, to use tea bags whenever my eyes felt tired. Hope this helps!