Get an idea of the content you'd like to post. You don't have to post nude (or even lewd) photos to gain followers. Only post what you're comfortable with, and stay as true to yourself as possible. There's no use in faking a strict domme persona when you naturally lean toward nurturing and caring qualities instead. There's a large audience for all styles, and playing up your natural qualities will make your experience much easier and less draining.
The best way to learn what content to make is to look up a tag for the kink you're interested in, and see what others are posting (ex: findom spit worship). Do NOT, however, outright copy posts and photos. That's a quick way to get mass-blocked and alienate yourself from the community.
We understand that there's only so many ways to say "send me money, subs," but get creative. Stealing a tweet word-for-word is disrespectful and lazy, and your audience will pick up on both immediately.
Instead, pick one of your features you want to play up, pick a specific color and theme all of your content, find something original and make it yours.
Be mindful that sites like ManyVids have strict rules about what content you can host on their site, and exclude a swath of edgeplay. Be careful what you post to avoid account bans. All restrictions are outlined in a sites TOS, or terms of service, which should be available by googling [Site Name] TOS.
Whatever you decide to post, good lighting makes a HUGE difference in photo and video quality. Invest in a ring light, phone tripod, and selfie remote to make your life and your content better.
Sessions, how you deliver content and services, can vary widely. You can do DM-only sessions, voice/phone sessions, video call/video response sessions, findom and femdom games, or sell content. Look around at other dommes menus to get an idea for pricing. Don‘t undersell yourself!
My favorite photo editing apps are Picsart (they have a 50% off student discount for their premium app, but the free version is also excellent) and Photoshop Express. Canva is also useful for making promotional material.