I am rather like a mosquito in a nudist camp; I know what I want to do, but I don't know where to begin.
Abundance can paralyze as surely as scarcity. The mosquito in a nudist camp has no doubt about its appetite; what stumps it is the sheer number of inviting options and no obvious first target. The joke turns on a familiar human predicament: clear desire, unclear starting point. Wanting something badly doesn't tell you how to take the first step, and when every path looks equally open, choosing one can feel like giving up all the others.
The idea sits close to what is often called analysis paralysis, and to the old practical wisdom that a big task becomes manageable only when it is cut down to a beginning. The line is credited to Stephen Bayne, an American Episcopal bishop, though I can't confirm its original source, and witty lines like this often drift between speakers. Its humor is gentle and self-mocking, admitting overwhelm without shame.
Someone today might feel this when deciding to declutter an overstuffed home or change careers. Rather than waiting for the perfect starting point, they could pick one drawer, or one conversation with a person already working in the field, and do just that this week. Almost any reasonable first move beats circling indefinitely.