dlyteful
told me that you earn those yellow and green marks through participation in a spot.
rating material, leaving lots of comments ,uploading images , submitting videos and asking questions and having those being rated and viewed. Stuff like that...

this might help

Medals
What are medals?

We felt like our users should be rewarded and recognized for their good deeds and contributions to the communities so we designed the medal system. Based on your activity within a spot you can earn different levels of medals. Think of the medals as a measure of reputation. The higher the medal, the more respected the user in that spot. These medals are awarded to those who regularly contribute quality content from:

posting highly-rated links, videos, images and soapbox articles
starting active forum topics and picks
and active participation


How do the medals work?

Each different level of medal reflects your reputation within a spot. Here is a table of the available medals:


Medal Level What it means
Dedicated Fan Respect from fellow fans! This fan has made some good contributions to fandom.

Die-Hard Fan Greater respect from fellow fans! This fan has made significant contributions to fandom.

Fanatic Mega respect from fellow fans!!! This fan has gone above and beyond the call of normal fans.


How do you earn medals?

We have a magic scoring system that we like to keep secret so that we don’t promote abuse or gaming from users. Fanpop is about collaboration, not competition. All you need to know is that if you keep on contributing great stuff to the spot, you will be rewarded accordingly. Think of it like getting that bonus present under the Christmas tree that you weren’t expecting from Santa. It's that much sweeter when you get a surprise.

Thanks!