Naturally, what you bring into the field with you is going to depend a great deal on where you are going and what you are doing, plus a large measure of personal preference. It is perfectly enjoyable to walk a trail with empty pockets and just observe what you encounter. Others enjoy an assortment of items that may come in handy. You should practice whatever level of preparedness you are most comfortable with (though a proper snakebite treatment kit means having at least a cell phone and car keys). If you are looking for terrestrial herps, a field hook will almost certainly come in handy.
This lesson is part of Certified Herpetological Guide. Enrollment is self-paced, with no deadline to finish (about 50 hours).