Step 1:

Load up rimworld

Step 2:

Click new colony

Step 3:

Select crashlanded survivors scenerio

Step 4:

Click "edit mode"

Step 5:

Customize the scenerio to whatever youd like, at an interesting story to the start if youd like more people to be interested.

Step 6:

Select "upload to workshop"

Step 7:

Customize your workshop page, and let the subscribers roll in