1. Sprint Everywhere until you hear something, then hit the floor if you're on a PC. Use a call while you crouch and you'll be beside an animal in no time.

2. Deer, Deer, Deer, Bear. Take down these early on, they go down fast with a clean spine shot - ♥♥♥♥ lungs because that's not what the game rewards you for - the exception for this is when you're hunting with a bow.

3. Quest. Get that sexy XP, the starting quests in both areas are pretty easy and give a ton of XP.
Don't worry about upgrading your weapons too much, the starter rifle does everything you need it to.

4.Double Tap. Once you get a few skills and perks, double tapping your shot is a breeze - hold your breath and get 2-3 more shots off if you need to take something down quick and minimize tracking endlessly. Note for clarity: Once you level up some you can stay in scope while reloading. This allows you to come back on target pretty quickly for follow up shots. I can't remember the perk/skill names but they should be self-evident.

5.Don't invest in a bow until you're ready for 'annoying/hard mode'.
Update Dec/17':
Bows work VERY well once you have a few callers and can lure prey back to you after a clean shot. Make sure animals are 10M~ before you shoot, swap to your caller and bring them back in. When you run in to a herd this is massive easy xp.

6. Coyote's + Foxes are easy game once you lure them close enough. Easy neck shots and easy money / xp. Note: Doesn't need to be a neck shot for these guys, a lung shot does the job for them too!

7. [Personal] Upgrade tracking not sitting around and waiting, unless that's your kind of thing. You'll find far more benefit early by quick shots and track down game easily with your proper perks.

8. Build stands when you can afford it now and then - the xp boost is easy and the money spend can wait.

9. Travel + Hunt. Aim to chase prey down toward your destination.

10. Spam your callers. This isn't classic where a call every 2 minutes is enough to do the job. Calls have something around a 40% chance to draw an animal's attention, wear off rather quickly and I haven't noticed that too many calls would scare animals. So if you are trying to call some sneaky deer out in the open get yourself a nice vantage point and hammer that call button.

11.A lot of the perks in the weapon specific skill trees work for all weapons. I for example almost exclusively use rifles at the moment but have put 1 point into the gun tree (i think) so I can reload while running. Take a closer look, you may be missing some pretty nice abilities because you disregard the skill tree they are in outright as the wrong category.