The steps for publishing a collector app are as follows:
- Design the .gdb
- Publish to agol / portal;
- Create a webmap
You'll need to do the schema design in #arccatalog - create your feature class(es), table(s), relationship(s), and all associated domains and subtypes. Once your schema is complete, you'll publish your data to agol; When this is done, you'll create a #webmap and make sure your symbology looks good and that your rules are all being enforced. A word of caution - #subtype defaults are not supported in the webmap / webapp, but will work correctly in #collector. As soon as you have a webmap up and running, make sure you've granted the correct permissions, and you should see your webmap in collector.
Feel free to PM me if you've got specific questions, but Esri has done a very good of making this process pretty easy.
