Draw two really short staves, add the G and F clefs, and then only draw note heads for which ever note you’re working on. I suggest doing them in this order. Start with the Five C’s and work out. Don’t move onto the next note until you can do the one you’re working on from memory correctly the first try of the day. You can always check your work by using the clefs, but, as soon as possible, try not to “count” up or down. Learn them spatially. D’s and B’s are just a step up and down from C. A’s and E’s skip to the next line down and up from C. F’s and G’s are a little trickier, but you should be getting the hang of it by then.
After you have a note’s position on both staves memorized, it’s a good time to reinforce your memory by taking the Tenuto tests I’ve made for you. The link is below each image.