Be a little careful about what kinds of arguments come to mind. If I run "look for the most obvious uncharitable insulting argument" on one of my current projects (writing a book), my oh-so-helpful brain immediately returns "It's arrogant for you to write a book. Also you can't finish a project this long. You're going to hit a hurdle and all the work will be for nothing!"
This, despite the fact that I've got a contract, my editor liked the first three chapters I sent, and I'm over halfway to the finish, look to be on track for deadline, and set aside a month of nothing but this at the end.
I'd suggest just being slightly more suspicious of insulting arguments that make claims about your character sucking (immutably) than ones about the way you've laid out the plan.
I do like this comment from "Die Vampire Die" as a countermeasure:
Who do you think you’re kidding?
You look like a fool.
No matter how hard you try, you’ll never be good enough.
Why is it that if some dude walked up to me on the subway platform and said these things, I’d think he was a mentally ill asshole, but if the vampire inside my head says it: It’s the voice of reason.
I'd suggest just being slightly more suspicious of insulting arguments that make claims about your character sucking (immutably) than ones about the way you've laid out the plan.
It seems katydee may have made a mistake in choice of language here by conflating "yourself" with "your plans". To nitpick, it might better to consistently refer to the thing to be strawmanned as "your plan(s), and not use "you" at all. If one wants to generate an argument to point out flaws in their own plans, strawmanning yourself is like lau...
One good way to ensure that your plans are robust is to strawman yourself. Look at your plan in the most critical, contemptuous light possible and come up with the obvious uncharitable insulting argument for why you will fail.
In many cases, the obvious uncharitable insulting argument will still be fundamentally correct.
If it is, your plan probably needs work. This technique seems to work not because it taps into some secret vault of wisdom (after all, making fun of things is easy), but because it is an elegant way to shift yourself into a critical mindset.
For instance, I recently came up with a complex plan to achieve one of my goals. Then I strawmanned myself; the strawman version of why this plan would fail was simply "large and complicated plans don't work." I thought about that for a moment, concluded "yep, large and complicated plans don't work," and came up with a simple, elegant plan to achieve the same ends.
You may ask "why didn't you just come up with a simple, elegant plan in the first place?" The answer is that elegance is hard. It's easier to add on special case after special case, not realizing how much complexity debt you've added. Strawmanning yourself is one way to safeguard against this risk, as well as many others.