All 5 Uses

however
in
Crank, by Ellen Hopkins
(Auto-generated)

I told Adam to come on over, I wasn't going anywhere then proceeded to fret, as I did anytime he and Lince popped up together in a single thought, anyway I had only this day to make him remember me, however I could.
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however = in whatever way
(At least that wasn't currently a problem!) The tattoo, however, was.

however = though (used to connect contrasting ideas)
I still needed answers, however.†

however = a word used to connect contrasting ideas as when using "though", "in spite of that", "in contrast", "nevertheless", etc.
The $500, however, presented a challenge.
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however = a word used to connect contrasting ideas as when using though, in spite of that, in contrast, nevertheless, etc.
Suddenly, However all those days with little or no sustenance hit me in one awful instant.†

Definitions:

(1) (however as in: However, complications may...)
though (or another expression that connects contrasting ideas)

Based on idea 1 we might not expect idea 2, but this is a way of saying that even though idea 1 exists, we still have idea 2. Synonyms include in spite of that, despite that, nevertheless, nonetheless, on the other hand, in contrast and but.
(2) (however as in: However much she tried...)
to whatever degree (regardless of how much; or whatever unspecified amount)
(3) (however as in: However you do it, get it done!)
in whatever way
(4) (meaning too rare to warrant focus)
Much more rarely (and arguably incorrectly), however can be used to intensify the word how, as when one says "However did you find her?" Grammarians would suggest using two words for that usage: "How ever did you find her?"