Hawk and Steve provide great advise. With your pup being only 8 months old, I would not use the ecollar at all while hunting, unless it is a real safety issue. Keep your pup on a 4 foot lead. When the pup acts up, pull her in close and tell her no. Make her feal comfortable. They need to learn that when you are hunting, it is work, not play. (They still have as much or more fun than you do). My female lab is about 1 year old and I have taken only her hunting with me everytime this year, she is always on a 4foot lead. I tie it off to my belt, when I am shooting, she is watching. When the bird falls, I let her off and she gets it, then its right back on the lead, right by my side. Try just keeping her on your hip until she gets the hang of it. If you have the ecollar on her, don't use it unless the pup is in danger. You want her to LOVE hunting, and not to remember getting hit/schocked while in the field. Use the ecollar for training and reinforcing well known commands only...
Best luck on your new pup!