When you start a new build, what is your go-to strategy for building? Do you start with the colours you want? Specific blocks? What types of thngs do you typically build and how does this affect your strategy?
First thing I do is figure out a few key concepts. Is it aboveground (like a house)? Is it in-ground (a hole in the wall or cave complex)? Underwater dome? Epcot sphere? Up in the air? Once I have those things set, then I go into a paint program and start drawing.
In the drawing program, I can fiddle with shapes, lines, curves, and other things without having to grind or spend resources. If I don't like how it turns out, or if I see a problem forming I can easily fix it or start over without potentially wasting resources. Once I have something I like, I can then relatively easily transfer it into Minecraft because the drawing program uses the same type of pixel-gridding that Minecraft does.
PROTIP: if you do decide to include a drawing program in your building toolbox, use a template file for your work. What I mean by a template is a picture file that has three core features: a large section in which to assemble and/or detail the main image you're working on, a smaller section divided into even smaller parts to work on various component/side projects separately from the main image, and a third really large area where you can toss finished component you can use later (this is referred to as a repository...think of it as a texture/image map you can take copies from to add to your image). You can maintain several templates for different structure types, allowing you to develop component repositories for each.
Typically I either still don't have a good idea of a final palette or the palette I chose has some accessibility issues for me to grind through. Assuming I have enough resources, I'll then start plugging in the color pieces. If I don't have a good idea, I'll pick something random to fill in one part (for example, the framing) and try that. If I like that, I'll pick another thing to go with it and see how I like the combo. If it's not automatically "gah! my eyes!" terrible I'll take a little break to just live with it for a bit to see if I come around. Rinse and repeat until the palette and the build is complete.