Cloudflare Security Configuration Needed

My site is already on Cloudflare, but the security section is still at its default settings. The immediate priority is to turn on and correctly tune Cloudflare’s DDoS protection so it works 24/7 without affecting legitimate traffic... (Budget: £20 - £250 GBP, Jobs: Cloud Security, Cloudflare, Computer Security, Internet Security, Linux, Network Security, Security Auditing, Web Security)