You actually can do it in standard notation - but if you've got more than a few, it can get cluttered. There's two methods:
1. Position notation - for example, if you want the notes C (2nd space from the top), E (top space), G (first space above the staff), CVIII would narrow it down to x-x-10-9-8-x, while CIII would give you xxx553.
2. String numbers - for the same example, 234 (each number circled) would be the 8th position, while 123 would be 3rd position.
As a general rule, I avoid trying to write specific fingerings in scores, because I think that's part of the interpretation. But sometimes a passage is a lot easier to finger in one place than another, or becomes really easy with a position shift... so I might write '2' in a circle over two successive notes to indicate a shift using the second finger.
But if it's just as a memory aid, chord blocks are quick and convenient.
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