You need to understand somethng of the essential quality of the three forms.
1) to + infinitive (This has a less direct quality)
2) the bare infinitie or infinitive without 'to' (this is very direct. That's why it is used in the imperative forms for example
3) the -ing or continuous form. This stresses, not only the continuous nature of actions but also some other things too.
Usually the verb following another verb takes the form TO + INFINITIVE. But you should try to feel the properties of these three forms rather than learn al the exceptions by heart.