Being able to tie a cherry stem into a knot is a sign that one is a good kisser/is able to work their tongue well
Notice the wordplay…instead of GIVING party favors which is what hosts usually do, Carmen is DOING party favors which may imply she is performing sexual acts with guests of the party (most likely for money)

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“Party favours” is also slang for drugs, most often things like ecstasy and cocaine (pretty self-explanatory, the types of drugs used to party as opposed to say, heroin), so “doing party favours” could mean that as well. My guess is that she’s using the double meaning intentionally.
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“Party favours” is also slang for drugs, most often things like ecstasy and cocaine (pretty self-explanatory, the types of drugs used to party as opposed to say, heroin), so “doing party favours” could mean that as well. My guess is that she’s using the double meaning intentionally.