I want to know I can get more sales by promoting my gig on other sites
You’re a graphic designer. If I were a graphic designer, I would think about all of the places where I could showcase a portfolio of my work to prospective buyers, and then link them back to Fiverr. Immediately springing to mind are Facebook, Instagram and LinkedIn. I wouldn’t spam using these platforms… I would focus instead on building a following by showcasing your designs.
You could create some tutorial videos on YouTube and link to your Fiverr profile at the end (so that when people feel that even with a tutorial the work is too complex, they might decide to reach out to you). You could cross-market these videos on LinkedIn, Facebook and Instagram.
And then there are the less obvious ones like Pinterest, Twitter, and I’m sure countless design-focused websites where you could showcase your design work.
I found a good topic here. Hope it will be helpful for you. Best of luck. Also I’m a new seller here too.