Higher share price
Share price is pretty meaningless to your own company after you have sold your shares, I wouldn't worry too much about it too much.
After the first week, c-rank position changes play a huge role in your share price. Companies which are improving their ranking will end up with a much better share price than a company who starts near the top and loses rank positions throughout the round.
There are a few things you can do if you want a higher share price, these involve trying to control your c-rank changes - especially helpful for share price when you are near the top of the c-rank.
For instance you could play the beginning of the round very slow to start off in a lower position, then after the first week gradually climb the c-ranking. This makes it easier to increase your c-rank position while avoiding losing rank position.
You could try to avoid improving your c-rank position by more than 25% in 1 day as anything above 25% is a waste if you are concerned with share price. For instance, going from rank 8 to rank 4 is a 50% increase but your share price increase for that move is limited to 25%. So for a higher share price you could try to move up to only rank 6 the first day (25% increase), then rank 5 the next day (16% increase), and finally rank 4 (20% increase).
When your c-ranking must drop, especially when you are near the top of the ranking, you might try to drop as far as you can in 1 day instead of spreading it out over multiple days. If your ranking falls by more than 25%, that part of the share price calculation is limited to 25% and you will have a smaller drop in share price than if you fall down the rankings slowly over a number of days.
One way to avoid improving your c-rank by too much at once is to spend money on things that do not increase your cv and also cause your cv to decrease when spending the money, like the salary account, fuel account, or buying goods that you will eventually need. These will reduce cv by 1 for each 20 that you spend, and push the cv increase into the future.