Prevention should start with maintaining shoulder and wrist strength. Strong musculature surrounding your elbow can help reduce the load on smaller forearm muscles.
The following are general preventive measures:
Take frequent breaks from activities that involve extensive wrist/hand motions
Limit repetitive grasping and gripping with the wrist and hand
Avoid lifting heavy objects with an extended arm
Reduce the overall tension of gripping
Avoid full extension and the extremes of bending
If you play golf or tennis on a regular basis, you should see a specialist who can advise you on how to avoid elbow injuries.