Hello! Congrats on your first post! To open a shop if you didn’t pick designer click this link Ribblr help center | Can I sell my patterns on Ribblr? How can I open a shop? to help you, as for selling/gaining traction I would recommend being active in the community as there’s tons of new patterns everyday and they’ll be easy to miss if you don’t specificly search for it but if you’re active your shop may have more of a chance of being seen
This is something I do for new users if I can 
if you ever need help never hesitate to ask in the community, if you need immediate answers feel free to use the help center, search in the community, or the wiki [link below] and community guidelines if needed Happy crafting! Hope to see your crafts soon as well