You need to create a job description that truly focuses on the exact skills and qualities you are looking for in the potential new hire. You need to define the right job responsibilities. You want this description to be truly in synch with what they will actually do, and the skills they actually need. This way when you are evaluating resumes, you will be able to spot strengths and weaknesses much easier. The performance evaluations should also be in synch with the skills and responsibilities within the job description. You will have to update the job description from time to time if there are any additional responsibilities, new skills, or new product experience needed.
Items that should be on the job description are:
For example, if you were looking for more of a Tier 1 support technician with lower technical capabilities than a Tier 2 technician, you need to be clear on the expectations in the description which will justify the lower rate of pay. You would create it around the skills needed for the position. You would not want to make a description with too many high-end requirements for a lower type of position. It might put off some potential good applicants. The opposite is true if you are looking for a higher end type of position.
You also need to keep in mind whether this is a non-exempt position (paid on an hourly bases) which would include overtime and is typically on the lower end of the pay scale, or exempt (paid on a salary basis) which is usually on the higher end of the pay scale but with no overtime.
The following screen shot is an example of a basic job description for a Tier 1 technician with somewhat lower expectations than that of a Tier 2 technician.