When the game first started players do not have a clue what to do or where to go. A chance for advancing can bit you in the ass before you decide to move.
If the field does not give an easy victory you have to win from tactical advantages, and attack the other team before the see it coming

Have a tactic or move ready to attack the other team so they dont have the opportunity to execute their moves and this will push them off balance giving you the advantage

Why not plan your moves ahead of time and try to come up with the best possible move, if you can go and check out the field and decide on where you should go first, and the next postion you should go next and so on.

Move to positions where you can work the field so you and the rest of your team can advance, when the chance comes you will alert and ready. If you do not have a good shot and the path to your next position is free then move. The more field you control the bigger your advantage

If you have a rather big field to advance from position to position you might want to have some cover fire ready from you team to help you advance in your position

If you bunker down and stay in one place you're letting the other team take control of the game, you're letting them have the advantage of who, when, where and how to attack, and while you plant your ass the other team is setting up there angles for advancement.

Check out the other team try to find their weak points and strong points this will let you know where you need to improve. (keep in mind there weakness is your advantage)