I went along the standard method I'd researched and created whilst in my last company. Seding an SEO proposal, honing the contract, then performing the SEO e.g. understanding the company, market, competition, best KWs, SEO hisotry, company goals etc. Getting a basic SEO plan sent to client, analysing the website for changes, performing them, then analysing their exeternal SEO potential and actioning that - all in relation to the goals set out at the start. Monthly reporting etc.