Medium - Fish salmon with your bow! you can fish Salmon with your bow. Just look at any low waterfall, and you have a nice chance that they are there. They are steady but quick, so this really helps with your timing. Good luck!
expert - Hunt rabbits! Rabbits are quick, unpredictable, and out of sight easily. No better training then hunting rabbits for a day! Want to make this harder? Spook them first, wait till they are almost out of range, and then try to shoot it.
General tips:
1. - Arrows make a noise when they hit walls and items. You can use this to draw enemy attention away fom you, allowing for sneak shots at an enemy's exposed back
2. - If you have drawn an arrow, but do not wish to use it, there is a 'release' key (R default on PC). Use it to save arrows and to avoid making unneccessary noise.
3. - You can easily capture souls by enchanting a bow with the shortest duration soul capture spell (1 sec). Even with petty soul gems, you can get many uses from the enchantment.
BONUS TIP: Get the arrow craft mod! I am not a fan of too much mods in a game, but i thought it did not make sense at all that you cant craft arrows. You can get it here: http://www.skyrimnexus.com/downloads/file.php?id=490
Thought this should help.
Ps: most awesome shot: shooting an air arrow after the bunny got away, and landed on top of him underwater. Came up floating a few seconds later. Yay <3.
