You've gotten some good advice so far. This from a PA Park Ranger who gives the rattlesnake program at Sinnemahoning:
Two types of people get bitten by snakes. Those who mess with them and those who surprise them. Don't be in either of those groups and the chances drop dramatically.
Rattlers are pit vipers, meaning they have heat sensor pits in their noses to sense the heat signature of prey. You are too big for them to eat so they're not likely going to bite you unless you frighten them. If they do, chances are good it will be a dry bite. 70% of human bites are.
As said, the snake kits are not the way to go. Stay calm, walk or be carried out, and seek medical attention ASAP.