0. Use a css framework like Bootstrap or Bulma, it's not difficult to put together a website/webapp with a bit of CSS skills (you don't need to know a lot of CSS to create a good experience)
1. Team up with the UI/UX designer who you've worked in past and offer them your backend expertise for their project.
Good ol barter has saved my ass multiple times by now.
2. If you don't want to get someone from your workplace, you can go on upwork etc...and hire a freelancer, it's a paid option.