How to fill out the Contra Costa County Employment Application Form? 1. Read the instructions carefully. 2.To assist Contra Costa County in its commitment to Equal Employment Opportunity, applicants are asked to voluntarily provide the following information. Contra Costa County only accepts online applications. When viewing a job posting for a currently open examination, you can select the option that says 'Apply'. This guide describes how to apply for jobs using the Career Page web site. The process consists of the following steps: Create an Account. Application Process - Completing and Submitting an Application. Form Number, Video, Date Revised, Form Name.