First, you need a good, up to date map of the trails. I'm going to use McKinney as an example because it's where I'm currently at. McKinney's official trail map is here, which is linked to from here. Here's a sample of the actual map (ignore the dotted lines - they are where the trail is eventually going to expand):
Note the official map is missing the numerous sidewalks in McKinney, some of them wide enough to accommodate golf carts. All are quite usable by e-bikes.
You may be tempted to use Google Maps, but its trail data is out of date. For example, the east/west path on Eldorado Parkway, and the north/south route on Valley Creek Trail are completely missing on Google's map.
Up to date "route intelligence" is key when planning new routes, so it pays to scout around to double check actual road and trail conditions. The metroplex this far north is still expanding rapidly, so new roads, sidewalks and trails are popping up all the time.
My goal is to commute from west McKinney to my office (at the historic Cotton Mill) and back, as safely and quickly as possible, while also avoiding dirt, mud, waiting at red lights, etc. In reasonable weather I can travel this ~6.5 path in around 23 minutes, or a few minutes slower in the rain.
The first route takes the sidewalks and subdivision streets to the Wilson Creek Trail, I take this trail to east McKinney, then I follow some low traffic subdivision streets in east McKinney to the office:
This path only requires a single red light crossing (at S. McDonald St. and Elm St. east of the highway). Try to beat that in a car! And if you're a little adventurous (and lucky), it's possible to cross McDonald without going to this intersection, making this route completely light-free.
If you're wondering why I choose to route through a subdivision at the beginning, it's because there are parts of Virginia Ave. that don't have trails or sidewalks. The traffic on Virginia is insane (at 40-45mph), so alternative paths must be found.
Here's a variation that minimizes the amount of time spent on roads at the beginning, but is longer. This was my original route, until I realized I could easily take a shortcut through a nearby subdivision:
My backup route is longer, but it has the plus of going past a number of shopping areas. This route avoids most of the flood plains:
The key bottleneck in all of these routes is crossing under highway 75. Highway crossings must be carefully chosen, because for whatever reason they tend to be complete high traffic disasters of construction, broken pedestrian lights, mazes of traffic coming from every direction, etc. My route uses a safe, very low traffic underpass that directly connects two parks.
Google Map's satellite view is also critically useful when planning safe routes (although be aware that it can be several years out of date). Here's the beginning of the route, showing exactly how you can use sidewalks and low traffic subdivision streets to your advantage:
My next post will demonstrate how easy it is to get to various interesting/useful places from west McKinney, without ever having to travel with road traffic.