Add a Signature:

Click the My Profile link at the top of the forums.

Select the Edit Profile link at the bottom of your profile information.

Fill in the Signature box.

Modify Your Display Name:
Click the My Account link in the blue band at the top of the screen.
Change your Display Name text.
(NOTE: At the present time, if you start a blog you don't have the option to use the Display Name feature. It only gives you two options - your sign in name or your real name. I'll update this info once the Display Name option is available.)

Go to First Unread Post in a Thread:
Click the My Profile link at the top of the forums.

Select the Edit Profile link at the bottom of your profile information. Within that page you'll see a preferences section. There's a checkbox next to Jump to First Unread Post. Check that and you're good to go