"fuddle yourself up" is a figure of speech for young or middle-aged people's disclosure of their secret attempts to entice a professor by engaging in sexual acts.
The term comes from the well know phrase "fuddle" which refers to cuddling while making love.
Fuddling yourself up is quite popular among college applicants nowadays.
Haley, why don't you go "fuddle yourself up" to that college professor. You might have a way into college then.
If you "fuddle yourself up", professors are more likely to write you a letter of recommendation.