If you want to learn grading yourself, take a handful of the same type coins, whatever you may have.
I suggest
Jefferson nickels, simply because you can find some older and more circulated examples still in circulation.
Examine each coin with a magnifier. Know what are considering the "high points" of the design.
Lie up the WORST condition on the left and the BEST condition on the right.
Keep sorting the coins until you are fairly sure that each coin in the row is where it should be.
You will have learned a tremendous amount by doing this type of sorting for any type of coin.