'Jacking up' is the state in which a person/hobo/fugitive finds himself somehow getting involved with injecting heroin, a really bad drug, also a really stupid way of ingesting a drug. 'Jacking up' is sometimes referred to as 'stabbin' da veins'
Jalentine posted a photo of himself 'jacking up' which means he is a real badboy and he also got a tattoo and now he is fell over because he did too much heroin.
A hardo is a person who tries extremely hard at everything. Most times a hardo will try very hard at things that do not require excessive effort. For example, sports practices, gym class, etc.
Wow did you see Jack at practice today? What a hardo!