1) Click the 'Saved Drafts' tab.
2) Locate the name of the organization and category for your draft. Click 'Continue' next to that draft.
3) You'll be taken back to your saved draft, which you can then continue to fill out.
In addition, if you are already logged in to your Submittable account and you return directly to the organization's submission form, you will see your prior form field entries filled in if you previously entered data and clicked 'Save Draft.'