Taking action has varying degrees of difficulty for every person. The factors are numerous. But in history, in life, in every scenario I've ever read or studied or watched, there's only one factor that matters: regardless of conditions, health, limitations, weather, whatever--the person made a decision and took action, over and over. In my experience, it's as boring as that. No mental hack, no shortcut--decision and action.
Sure, you can work on 'clearing obstacles' to getting things done--mental models, physical problems, whatever--but you don't wait for this to be 'solved'. You have to act. And do it again until you're done.