Skinny Al said...
Where do you live near?
Buy a second hand board built by a shaper that is reputable, about 4 or 5 inches bigger than you are.
No less than 18&1/2 inches wide and no widder than 19 inches would be general guidelines.
but it depends on where you will surf mainly and how good you are and what you want the board to do.
You'd probably want something a bit bigger then the above mentioned, if you've only been in the water for a weekend
Just get an old watertight board that is about a foot taller then you, wide and thick rails (maybe a mini mal)?
Then when you grow (skills) past that, buy the above mentioned board and shred