Great question! I'll walk you through; keep in mind that if I tell you to go in a particular direction, but there's a blank wall, you'll ned to bomb. Here goes:

From your starting point, the first room of level 9:

Up 2 screens
Left 1 screen - Take the passage way; From where you appear go:
Right 2 screens
Down 2 screens
Right 1 screen
Up 3 screens - Take the passage way to get the Red Ring.
Down 3 screens
Left 1 screen
Up 3 screens
Left 1 screen - Take the passage way; From where you appear go:
Left 2 screens - Take the passage way; From where you appear go:
Up 1 screen - Take the passage way to get the Silver Arrows. ****You MUST have these to defeat Ganon!!!****
Down 1 screen - Take the passage way; From where you appear go:
Up 1 screen
Left 1 screen
Up 2 screens - Take the passage way; From where you appear go:
Left 1 screen - Take the passage way; From where you appear go:
Up 1 screen - Welcome to Ganon!

There you go! Good luck! (P.S. To help you follow along, you can find a gif map of this level at http://db.gamefaqs.com/console/nes/..._dungeon_09.gif - It's very helpful and even shows you what critters you'll find in each room.)

TKTOYUL;P