I am trying to stick to the pretty much universally recommended way of doing this and that is to use only quads. Not triangles.
There are several articles online about why quads work better. Here's a link to just one explanation but a quick search on Google will find you lots of others. In short, quads can be smoothed, quads maintain edge loops and can be subdivided for improved quality results.
Most balance articles also mention that there are cases for using triangles in some parts of the model but they should be hidden out of sight. I now know why I found it so difficult to get smooth faces on some of my earlier models. I'd used triangles in the wrong places.
From a games perspective, most, if not all rendering is done as triangles but we are talking about the best way to create the model. Quads, apparently also animate better because the folds will be more predictable.
Anyway. The point of this post is to remind myself of how I have made some shapes with quads, avoiding triangles.
At the moment there is just one tip but I'll add more as I work them out.
- Reduce the number of edges subdividing rectangles
This transitions from a row of three quads down to a row made with just a single quad. A complex shape at the bottom of the face and simplified at the top.
I often end up with this situation when creating curves within otherwise flat faces.
Another example, 10 quads down to just two.
Other useful articles and tips:
What shape should the quads be? Evenly sizes or any shape.
Also look for edge-parallel mode. After pressing Ctrl-R for a loop cut, press E to align to an edge and F to toggle between which edge to align to.