"Should I dress up to go to church?"
As the old saying goes, "When in Rome do as the Romans do". I have been to churches where men wear three piece suits and women cover their heads. I have also been to churches that seem like a "come as you are party." In general, though, this is a matter of taste and not theology. Certainly God loves you as you are. But do show some respect for the customs of the community with which you are engaging.