Gmail – Forward an Email in the Reply to Another Email

You can set up a filter so that no message is sent to the spam folder:

1. Settings → Filters → Create a new filter
2. From: *
3. Create filter with this search
4. check Never send it to Spam

From there, you can set up your email forwarding.

Sure, and it's pretty easy too:

1. Go to Gmail settings
2. Go to Accounts and Import Tab
3. Click on Send Mail from another address
4. Enter the Forward account address.
5. The email should send to that address which should forward back to your Gmail.
6. Complete the steps in the email.

When you send a new email you can now change the from address to your forward account.