Bathing, applying perfume, and similar preparations are merely sunnah. A pilgrim may do them before boarding the plane, and if he enters a state of ihram without them there is no harm. He should form the intention and recite the talbiyah while seated on the aircraft as it comes in line with the miqat—or slightly before—ascertaining this by asking the crew, careful enquiry, or estimation. Having done that, he has fulfilled what lies within his ability. If, however, he is lax and unconcerned, he errs and abandons an obligation without excuse, thereby detracting from the merit of his Hajj or ʿUmrah.
Anyone who passes the miqat without ihram must return to it and assume ihram there, for it is a duty he can still make up and therefore may not neglect. Should he refuse to go back and instead don ihram from Jeddah or any point nearer than the miqat, he must offer a compensatory sacrifice: slaughter a sheep, or provide one-seventh of a camel or one-seventh of a cow, and distribute the meat to the poor of the Sacred Precinct, taking none of it for himself.
A Muslim must give due care to his religious affairs, performing every act of worship in the manner prescribed by the Law. That includes assuming ihram for Hajj and ʿUmrah from the places designated by the Messenger of Allah—peace and blessings be upon him—and not passing those points unless already in ihram.