“Here is a link to a bunch of general and team specific strategy guides, I hope they will be helpful.

http://www.blood-bowl.net/Tactics/BBTactics.html

Some basic advise I would give;

Unless the situation is desperate, try and do all the easy actions first that require the least amount of dice rolling. Stand players up, move players that don't require dodging etc. etc. Try to maximize 2 dice blocking with assists, it was difficult against my lizardmen because I had 4 strength 4 players but against other races it should be easier. Try to keep your blitzers off the line of skrimage unless you are against a weak(er) opponent. You don't always have to try to smash your opponent, a lot of the time you can simply put linesmen at the front to get beaten up. This keeps your opponents team tied up with your linemen and allows your movement 7 blitzers freedom to move and blitz around the pitch.

You really need more rerolls. 1 reroll per half just doesn't cut it because things WILL go wrong at the worst possible time. I personally wouldn't start a team with anything less than 2 rerolls and if you can afford it, 3 is even better. I think an ogre at the start is slightly unnecessary and expensive, if you had a basic linesman in his place you could afford another reroll. With humans you are going to face quite a few teams that are stronger than you and a single ogre really isn't going to help you all that much, the strength of the human team is in the blitzers, throwers and catchers. ”