shipon_pgmr

Fiverr doesn't disclose their search algorithm. But you can get the best results by using Google Keyword Planner. (You can find many websites for keyword research. But Google is the best among them. You will go to the google keyword planner and select "Discover new keywords" then from there, you can search with the keyword and specific site link with the country. After clicking "get result" you will see how many monthly searches are on "avg. monthly searches" column.) note: You must know how to use Google Keyword Planner without creating an ADS campaign.

I think (Graphics & Design > Email Design) is the best category for email signatures. Because there are most of the required gig-related topics here.