Speed Optimize my Website

I have several websites that I would like to have optimized for speed loading. They are all WordPress websites. You can not add or remove plugins. All work must be done in a child theme environment. Please send me a list of websites that you have optimized for speed. I will not respond if you do not provide a list of websites you have optimized. Do not waste your time sending me a copy/paste response. Prefer USA freelancers or a freelancer that works USA times. Please feel free to ask any questions you have.