Variable Product

Hi. I try to put some variable at product(Size :s/m/l and xl) and i can’t.
I was following more tutorials but don’t work.
What i do?
New product> Add some info about product> Product data> Variable product> Attributes> Add> Write “Size” at “Name” field> Values : S|M|L|XL>
I select “Used for variations”> Save attributes> Variations> Add variations
(and i try with Create variations…)> Save> Publish and when i press on the “Size” field of product page just appear “choose an option”.
I use woocommerce.:)