Try pre-writing. Getting something onto paper is a good start. Once you have something, tweak it a little so that it flows conversationally. It might sound insignificant at first, but my truly ingeneous comics that everyone agrees are funny were done in this manner(and after splitting the field as to whether I'm funny or not, getting a general consensus lets me know I'm onto something good).
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If you do just one thing in life, then you need to get out more and expand your horizons. Honestly, that one thing can't possibly take-up all your time.