Fresh collards often have a lot of dirt on them and it is very important that you get it all off or your pot of collards will have a gritty texture. The best way to clean them is a two-step process. Fill your CLEAN sink with cold water and place the collards in the sink. Dunk and swish all of the leafy greens several times in the sink. Drain and refill with clean water. The second wash is when I look at each stem and leaf to make sure it is clean and then remove it from the sink onto a drying rack or a cutting board if cutting and using right away. If you get the fresh cut collard greens in the bag that are already cut, they are usually washed, but I still dunk them in cold water and move them around before using.