I find it so hard to remember all the stages/things happening in meiosis and mitosis and how to describe how they create variation

Any tips for remembering these especially like the whole segregation/independent assortment/crossing over and how these link to the stages


I would strongly recommend learning the definitions of each of those terms first and then explain how they contribute to genetic variation in the gametes.
Questions are more often based on how meiosis (and sexual reproduction) contribute to genetic variation within a population. The depth of explanation would be a step-up from level 1.

Crossing over
This is when the non-sister chromatids cross over and exchange genetic material.
This allows recombination of alleles within a chromosome.
Hence, alleles that were originally inherited maternally or paternally are now recombined on the same chromosome.

Independent assortment
This is when the pairs of homologous chromosomes line up and separate randomly into gametes (during Meiosis I).
This allows for variation between chromosomes, hence new combinations of (unlinked) alleles can now be produced.

This is when the homologous chromosomes separate, thus separating the pairs of alleles.
This allows each gamete to receive only one allele for each pair, and thus ensuring all daughter cells are unique.

Hope that helps.