Etsy sales ebb and flow so unpredictably. When this happens to me, I do these things:
Etsy-related:
• Make new, different items (and post them)
• Make larger quantities of best-sellers
• Work on my photos
• Update my tags, titles, descriptions, policies, profile, and shop announcement
• Make a treasury
• Participate in the forums and teams :)
Non-Etsy-related:
• Write new blog posts
• Post on my Facebook business page
• Research and apply to new brick-and-mortar boutiques
• Research and apply to craft fairs
• Order supplies
• Tidy my workspace
...Basically I just use the time to re-group and re-invest. Slow sales times are great for catching up on all the things that get neglected when your shop is buzzing with sales, so be encouraged that things will pick up again and you'll be glad you did all the other stuff while you had time. And sometimes those very things are what get you noticed and end your dry spell! Best of luck to you!