Alternatively, you may roll over an old 401(k) into a new account with your new employer; begin taking distributions; cash it out entirely; or roll it into an IRA.
If you have more than $5,000 invested in your 401(k), most plans allow you to leave it where it is after you separate from your employer.
Make sure that your new 401(k) account is active and ready to receive contributions before you liquidate your old account.
Of course, you may decide you'd rather just take the cash and run.
The process for withdrawing funds to your bank account is relatively transparent, although you will need to liquidate any securities held in the account before you do so.