Help with My Final Fantasy Tactics!

Could you please tell me ways on what are the most preferable early jobs to get. I'm just sick of failing missions!

Random battles are your friends. Since you need to get to certain job class levels in order to gain new jobs, try and do as many random battles as you can. Also, learn the skills on your equiptment.If there are quests about certain jobs, do those. They generally give good rewards.Early on in the game, Monks (bangaa) are really strong, and continue to be usefull throughout the game, so get one of those. Archers aren't very usefull unless trained in a high STR class, like warrior, first. So if you want an archer, level them as a warrior for a few levels first.