1. Depends on your starting team and your starting reputation.
Assuming you are a rookie manager with no experience then morale boosts take longer. Morale boosts come differently for different teams you manage.
If you are managing a top side, then it will take a long time. Winning pre-season friendlies is not enough. You NEED to get consistent results. If you are a top side, then winning every match is crucial. Big wins are more important.
If you are a poor side, then that process takes much faster since the expectations are lower. Look at your Assman Feedback for teamtalks as a good guide. The feedback there is enough.
2. There are other factors at play too and you need to control them as much as possible
a. Choice of captain.
Choosing the right captain is important..it not only gives a morale boost to the player in question but to the rest of the team.
b. Giving players a run in the team
If you have players that are in the first team, and that is reflected on their squad status, then you need to play them in as many matches as possible. Rotation for 1 or 2 games is fine, but if you don't use them their morale dips.
c. Media talks
The best option for any media talk has to be "no comment" in most cases it does not affect your morale going into a game that much. However when you choose the wrong option, then it can have an adverse effect on morale, creating a waterfall effect that affects the match as well.
d. Teamtalks
Teamtalks are vital in this game, leaving them to the Assman should NEVER be an option if you want to be consistently good. No matter how good an assman you have, they sometimes give the worst possible team talk and this can be hard to turn around. The best thing to do is to give individual teamtalks. If players have the same starting morale then its fine to group them together. Its not always easy giving the right talk but you need to learn how to do it.
e. The game itself
Scoing an early goal, gives an unfair morale boost imho. As does a keeper who makes 2 point blank saves in the early minute. Use this to effect. Against top sides, you need to decide whether to stick to your guns and play defensive. But don't do it for too long...the reason why:
When you are playing a strong team, the longer that team takes to score the greater the effect on their morale. The players can get de-motivated. So time your attacks and switch to attacking mode by pushing up your dline, and attacking them. This is my
fav way of handling sides like chelsea. You can take several approaches. In some games I go attacking and put a lot of pressure on them score the early goal, then go to a normal dline, narrow, tempo to normal and turn on counters. Their morale dips, mine will soar. At halftime...if we are leading by a goal..I will encourage my players. If we are leading by two I keep quiet and only talk to those whose morale is not superb or those who have 6.
f. Player interaction
If you decide that you want to say something to a player then be aware that this can have a knock-on effect. Understanding player personalities are important so you can give them a morale boost. If someone is a great player, has a determined personality and is giving you 6's...then tell him his performance is sub-par and he will get fired up for the next game...a morale boost. But!, if your tactics are bad this could backfire. ONLY do this once you are certain your tactic can bag you good scorelines. This usually happens in midseason when your team has developed excellent understanding and it translates to your tactics.
Morale is a big part in this game. Managing it through the Assman should never be an option for anyone hoping to be consistently good. Those guys out there who become good at this game rarely use the Assman option for teamtalks. Learning how to do it now will help for FM2008.