Endeavor to cut long straight lines and curves without stopping, because a small bump or ridge often results where the cut is interrupted. Try to use the entire blade for each cutting stroke, except when you are approaching a stopping point, but even here keep you sawing movements as smooth as possible. Cut the blind sections first, and for that matter, if you have delicate sections that are not blind, try to cut them first as well. As your skill improves, your pace will quicken, but be careful not to cut too fast because the blade will heat up and break. The other principal reason blades break is that they bind in tight corners or from being forced to turn too tightly to follow a tight curve.
Blades also break when the metal fatigues from use, or simply because they get dull.
Again, be sure you have lots of blades on hand. Blades usually just break without causing problems, but I have had partially-cut inlays break when the blade broke. Once in a while a blade piece will fly when it breaks, hence the recommendation to wear goggles. The blade can also loosen somewhat during the cutting, which actually makes it easier to cut but it wanders aimlessly. Be alert for this and tighten as necessary.