Check on how much you are contributing. Make sure that you are contributing as much as you can, as often as you can. Remember that if you are 50 or over, you can contribute an extra $5,000 a year to help you get retirement ready faster. This is a great thing to take advantage of.
Make sure your beneficiary information is in order. Sounds obvious, but it would be a horrible thing to overlook if there are changes that need to be made. Make sure that you have a knowledgeable and trustworthy CPA to go over your 401K with you. They can help you make sure your investments are diversified and that you are not taking in too much of any one stock. Also make sure your investment choices haven't drastically changed from the last time you checked on your 401K.
If, after giving your 401K a good check up, you feel like it is not working for you, seek the advice of a seasoned professional. There are so many options out there right now and you want to be doing the best thing for you and your business. These are just a few simple ideas for giving your 401K a check up!