After I've decided how the flow of the map and a general layout has been painted out I get stuck! Exactly how to use the splines/splats/tiles isn't the problem here. (Tutorials on how to use them are plenty.) The problem is that I don't know how to proceed really.
Here is an example of a map I've just started up.
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Territory points are out, black areas will be inaccessible terrain and the hedges is where I'll have sight-blockers. At this point I feel like I know how the map will play-out and what kind of look I want to give it.
Where do I go from here? How do I go about creating maps efficiently?
Do I continue doing basic tiles etc fleshing out the map before I go into details, or should I simply start in one corner, creating the map sector by sector?
How do you develop your maps and how do you suggest I do it?