This is my first tab so it can be wrong

Play this:
G|-------------------------------------|
D|------7-8-9---------7-8-9------------|
A|7-8-9---------7-8-9-------6----------|
E|-------------------------------------|

and throw in this sometimes:
G|-------------------------------|
D|----------2-5-4----------------|
A|----2-5-3-------5-----------5--|
E|--3---------------------2-3----|

Rate if you want to
BTW great song by Led zeppelin