1. If this is you'r first project, dont. It is possible to make an RTS but i can't recommend doing it as an first project, why? Because im trying it myself.
And if you aren't willing spending much time, then you shouldn't even begin, just to give you an idea, i've used 250+ Hours only in C2 working on the events.
I don't want to say that you can't do it or anything, it's just not recommendable as a first project, since you will have to redo much after some time, since you gain experience over time, and find better ways to handle stuff, that can be pretty annoying
2. Have a "Test" project, where you test mechanics and other stuff before implementing it, since you cant break anything there while testing how it could work.
3. Take a look at the sample .capx in C2 for RTS
4. Take a look at my devlog for my RTS, I continually post new stuff how to do some things, maybe you have an idea what i could explain next
(https://www.scirra.com/forum/shadows-of-war-rts-wip-devlog_t94686 )
5. Always keep an eye on the performance.
6. If it's going to be an big RTS you should only focus on using Node-Webkit as making a big RTS for the browser/mobile performance-wise wouldn't be a good idea.