Aside from obvious safety concerns, such as dressing for the elements, being sure your vehicle is in good working order, making sure you don't get stuck when bad weather comes in, taking a friend fishing with you, and not falling in, here are 5 tips for winter fly fishing.
1. Fish deliberately. The fish are moving slowly, and as such, a slower, more deliberate approach is necessary. Don't give up after the first cast to a promising looking spot.
2. Use midges and streamers. They are the most common winter food source.
3. Fish tailraces. The more constant year-round temperature of water coming from the bottoms of reservoirs makes them much more consistent.
4. Fish in rivers with brown trout. Based on personal experience, I have found that brown trout are generally the most active of the major trout species in the winter.
5. Fish on the other side of the equator. Remember, it's summer there.