Most rhyme schemes are denoted by letters. For example: a b a b means that the third line rhymes with the first and the fourth line rhymes with the second (in a stanza of four lines). There are many variations of this. As suggested above, read lots of pre 1960 poetry and work out the schemes, using a new letter when a new rhyme is used in the same stanza. For example, in a six line stanza it could be abacc (using a rhyming couplet at the end of each stanza, a bit like a sonnet).
This is how I was taught to scan during A level and at uni. Here's a witty, rhyming poem of mine, note the use of rhythm too, which is always something to bear in mind as there are many metrical choices usually denoting by stressed and unstressed 'beats'.
https://www.youtube.com/watch?v=__ko...8-R4gTJ-eSBPkg