From a Home screen, navigate: Apps icon > Contacts.
Tap a contact.
Tap the Edit icon (located in the upper-right).
Edit the appropriate information then tap Save (located in the upper-right).
To change the account type, tap the Dropdown menu then select the desired account (e.g., Phone, Google, etc.).
Depending upon the account type, the options presented may vary.
To add a pause (a 2-second delay between numbers) or wait, tap * # ( then tap Pause or Wait as appropriate.