Writing category descriptions for product website

Hi guys,

I am currently dipping my toes into SEO. I am working with a company thats handling things such as back linking, editorial posts, blog posts, meta data, etc. But due to budget constraints, i am left to write the category page descriptions and the individual product descriptions. I have about 25 categories and 350 products.

I have reas many articles, tutorials, etc but i thought i can come to you guys as well.

1. Any tips for writing category page descriptions for retail products? Specific word count needed?

2. Do individual product pages carry as much weight? What is there to know when writing these pages?