Polonius is addressing his servant Reynaldo in Hamlet act 2, scene 1 and is giving instructions for how he is to bring money and news to, while also checking up on, Polonius's son, Laertes. In Polonius's typical verbose style, he gives a rather confusing description of all that Reynaldo is to do as well as what he might expect to find when he reaches Laertes. Specifically, lines 62-65 demonstrate his desire for Reynaldo to be secretive about his reason for coming, as he says "we of wisdom" (including himself) are. The tone of the lines is also interesting because he is speaking about being unforthcoming in the same manner, which creates a sense of irony. His line "By indirections find directions out" is a clear example of this irony.
Overall, Polonius's speech contributes to his characterization as a rather foolish yet caring father who is known for circumlocution. In the grander scheme of the play, this series of lines illustrates the broad theme of appearance versus reality that Hamlet refers to several times throughout the play, including in his famous monologue in act 1, scene 2.