A lot of SEO Companies and Professional Freelancers have
a terrible way of managing their clients, time, seo tasks, etc.
I use something that is called a CRM (Customer Relations Manager).
There are many forms of Customer Relationship Managers or CRM’s but
me being a huge fan of open source, I use something that is called
Suger CRM. I keep track of all of my SEO clients and no SEO client
of mine falls through the cracks. You may download a FREE Community
version @ http://www.sugarcrm.com/crm/download/sugar-suite.html