When should you use the subjunctive?

To try and tackle this, my teacher taught me to use the acronym WEDDING:

WISHES - using verbs such as souhaiter que or préférer que to show wishes of one person for another person. EMOTIONS - an expression of an inward emotion, such as être triste que/content(e) que. DOUBTS - an expression of a lack of belief, using verbs such as douter que. DESIRES/ORDERS - if you want someone to do something, whether you use vouloir que or perhaps a verb for giving orders, such as exiger que or ordonner que, you must use the subjunctive. IMPERSONAL PHRASES - these are little phrases that one would use in specific situations, and they must be followed by a subjunctive. These include phrases like bien que (although) and afin que (so that). However these can be tricky because other words such puisque (since), look as if they should fit into this category, but do not take the subjunctive. NEGATIVES - the verbs croire, penser and espérer take the indicative normally, but when used as a negative construction, take the subjunctive: 'je ne pense pas qu'il soit ici', for example. GENERAL UNCERTAINTY - as a rule of thumb, if the subject of the verb cannot say with more than about 70% certainty that something exists or will take place, the subjunctive should be used: one would say that 'il est certain qu'il sera ici demain', but if you were unsure, you would say 'il est possible qu'il soit ici demain'.