The best way to get feedback on your work is to comment on other people's work and open communication with them (comment, follow them, shoot them a private message, etc). The more insightful comments you leave other poets with the more likely they will feel inclined to view your page and provide you with the comments you are looking for.
It is all about making connections and networking. You can wait for people to come to you, or you can reach out and take the initiative.