To "maximize" simply means to increase one’s position to the optimum level possible, in other wards to make the best use of one’s singleness.
The second word that is of importance is "singleness". This is a period that signifies you as a bachelor or a spinster (i.e) someone who is yet to get married. It is essentially good to maximize our singleness because of the importance of that period in a man’s life. God has never made any mistake creating man and the different periods of his development.