Selecting and Numbering the principal chain
Selecting the principal chain: choose the longest continuous chain of carbon atoms consisting of the principal functional group and maximum number of secondary functional groups and multiple bonds, if any.
Numbering the principal chain: Number the principal chain in such type of a way that the principal functional group acquires the lowest possible number followed by double bond and triple bond and the substituents, that is as follow:
Principal functional set > double bond > triple bond > substituents