It's easy to forget, but it's okay. I am here to give you a gentle reminder.
Why not spend a minute for a quick browse of those using the #upvoteplankton tag?
I am seeing some posts on there that definitely deserve a few more votes than they are getting. You don't have to go through every post, just take a scan, have a read of anything that catches your attention and leave an upvote, even small votes all make a difference!