Once you create a custom form you’ll want to use it on a page (or many pages). To add a form to a page or post go to the page or post (or create one). You will need to be in the “visual” editor mode. Right above your editor toolbar there is an area that says “Upload/Insert”. To the right of those words you will see some icons. the one on the far right is for adding a form to your page. (When you mouse over it it will say “Add Gravity Form”.
This will bring up a “pop up” window with a drop-down list of all your forms. Choose the one you want on this page/post and then click insert.
Tada! Your page or post now has your custom form embedded!