

https://www.marxists.org/archive/lenin/works/download/what-itd.pdf
https://www.marxists.org/ebooks/lenin/state-and-revolution.pdf
tldr build parallel power structures under the purview of a revolutionary socialist organization outside of the current bourgeois democracy. Strengthen them and grow them out as long as the bourgeois state allows, then in a moment of crisis seize state power to oversee a transition from capitalism to socialism.
There’s also the anarchist strategy which is similar in essence but with the crucial difference of laying out the parallel power structures horizontally such that no central power nor state organs exist.

I mean, yeah