how to increase my rating?

Tweet

i find many mylot members have a differet color star up their picture.does the color express a rating?is the blue color a highest rating?but i see that some people are just to post 200 responses,and their color is blue,the number is 10 ,but other people post over 300 responses,and their color is just a graym,number is 7. do you tell me what happen between two people with the some post but a different color of rating?and how can i do to increase to my rating?