Step 1: Determine if you need coverage for you.
Step 2: Determine if you need coverage for your spouse
Step 3: Calculate your coverage requirements:
- Amount of coverage
- length of time you will need coverage
- how long the money needs to last.
When determining these requirements don't forget the basic cost of living; also include money to pay off a house, or to pay for the education of children.
Now determine the sources of this insurance. Yes you can take advantage of insurance offered by your employer. Some provide free coverage for 1x your pay, or a set amount. Some offer the ability to buy coverage in multiples of your salary. I have seen up to 6X coverage, but it likely varies. Some also offer coverage for a spouse but those rules are different: they may be only for a set amount.
There are benefits to purchasing coverage through your employer. There generally is no requirement for a physical. The decision is annual, so you could decide to drop the coverage if the coverage is no longer need, or you can decide to increase it.
There are some cautions. Some programs only waive the physical if the coverage is under a certain amount, or if you hadn't waived the insurance in a previous year. You need to understand what happens if you leave the company, or if you become disabled. The costs could change, or even the coverage could go away.
Purchasing term insurance from an insurance company not related to your employer has some benefits: it can be purchased for 5, 10, 15 up to 30 years. The physical is only required when you purchase the policy. If you change employers you don't have to get a new policy. Also an employer could drop a benefit. Many term policies have options to extend the policy or covert it to whole/Universal life if you don't think you can pass a physical if you need insurance at the end of the term. The advice is to avoid "permanent" insurance but the conversion option might be important for some situations.
Purchasing a policy with a long term can also be more expensive. In the early years your rates are higher than they would be with a shorter term, so that in the later years you still have the coverage you need without an increase in rates. It becomes expensive if every few years you cancel a 30 year policy becasue you want to switch companies, or you want to change the insurance amount. You keep paying for the expensive years.