Hit the brakes and don't swerve into on coming traffic.
HIT THE BRAKES AND DONT SWERVE AT ALL, IF YOU HIT THE DEER TOO BAD
???
if its in the country most likely its a 2 lane road
one side is on coming traffic; this is self explanatory
on the other side is most likely a ditch, which getting THAT repaired costs way more than a deer hit
and if you're going fast enough, you also have a chance of flipping or rolling of you swerve
moral of the story dont loving swerve
its better to hit a deer than hit a tree or an oncoming car or flipping your loving car