I am currently using a combination of the rating system provided by Goodreads and this added explanation:
5 stars (it was amazing) – binge read so hard, would read again and want to tell everyone about it
4 stars (really liked it) – satisfying and made me read quickly
3 stars (like it) – didn’t read as quickly as others, didn’t knock my socks off but enjoyable
2 stars (it was ok) – was able to finish it but most of it just didn’t do it for me
1 star (did not like it) – finishing it was very difficult and I wanted to DNF
If I don’t actually finish something I’m not going to rate it.