If you click the link to the community front page you will see a tab that says write a post. The following image is off my phone not laptop but the principle is the same.

Also, if you subscribe to the community it will be in a drop-down box when you go to draft a post. You select the community you wish it to be in and go from there. You will need to subscribe to the community though.

Again, off my phone.

This assumes you use Peakd.

I hope this helps. Link to the community below.

THE WEEKEND