Analytical Procedures for Service Firm

Hello Everyone,
This is my first time working as an auditor and i haven’t sat yet for my F8 paper, i am a bit confused with auditing my first firm, which a “recruitment agency” service type of firm. I am performing my analytical procedures at the planning stage and i am a bit confused on how the ratio analysis, is different from a company with products and the company I am auditing.
for example recruitment services provided is different from products sold in a supermarket, where by Products doesn’t quickly turn into cash.
PLEASE I NEED HELP!”How can I draw conculsions from the ratios calcualted based on the type of company i am audiitng
Thank you and good luck to all who is sitting for F8.