The best way for an employee to preserve his or her future claims is to make a complete record of it. Make a record everywhere. Record the events in your daily journal. Report the events to your supervisor. Report the events to human resources. I know, reporting things is scary. You might get fired. But, if you do not report the events that you believe are unlawful, then you cannot thereafter hold your employer accountable. In other words, an employer cannot fix what it does not know is wrong.
I receive many calls from employees who were recently lost their job and were handed a severance agreement to sign. Some clients believe that the severance agreement is some kind of bribe; they believe it's an admission by the employer that the employer did some wrong; they think they are being silence. None of this is necessarily true. From an employer's perspective, a severance agreement is a smart move to protect itself against future liability.
For any size business, it is important to understand the difference between a volunteer, independent contractor and employee. Businesses often try to cut corners by telling their "employees" that they're really independent contractors while still treating them as employees. Small businesses, in particular, often run into traps when they hire "volunteers" under the belief that they are providing education in exchange for labor. Below is some general information about the legal definitions of a volunteer, independent contractor and employee. The most important fact to remember is that what an employer and the subordinate individual agree upon is not sufficient to change the subordinate's legal status under the law. In other words, you cannot contract around these legal definitions.