Hey, welcome to DA! Some things I wish people had told me when I first got started:
Tag your work! Look at the categories and topics and tag accordingly. That will make your work more visible.
Post art regularly (but quality over quantity) - Be active - Comment, fave, give llamas and Watch other deviants.
Use the ThumbShare Forum (https://www.deviantart.com/forum/showcase/thumbs/) I’ve gotten more watches and likes from this than anything else I’ve done here.
Join groups! Find some that cater to your likes and share (Some that have worked for me: https://www.deviantart.com/global-artz, https://www.deviantart.com/arts-vs-photos, https://www.deviantart.com/art-acceptance)
Check out the DA Welcome Wagon (https://www.deviantart.com/dawelcomewagon)