Tempo only applies to actions taken within measure. If you are not close enough to wound or at least take some sort of advantage, you are just moving.
A tempo is the time it takes to make an action with the understanding that you cannot make two actions at the same time.
Make sure the tempo of your attack is shorter than the tempo your opponent gives you. If it is longer, he will have time to parry.
Watch your opponent’s feet when in misura larga. If he doesn’t move them, his tempo will be short and he has the option to break measure. In this case, use the tempo to gain misura stretta.
If he moves to settle his feet, it is a good tempo for attacking.
It is easier to attack if your opponent doesn’t realize he is giving you a tempo. Watch for distractions.
In misura larga, you can sometimes take advantage of tempo when the opponent doesn’t move his feet. Surprised, he will be unable to parry or counter. Well doesn’t that sound like the opposite of what he just said.
Care, some will make a tempo to lure you into making an attack. Make sure you have time to strike and be ready to change lines if he counters.
In misura stretta, any slight movement at all should be taken as a tempo to attack, except moves to break measure. In general, making the first move in this measure is bad idea unless it is an attack.
In misura stretta you don’t need a tempo if you planned ahead and have a good counter-posture. Be sure that his sword is far enough away that he doesn’t have time to properly parry and if he finds you, it will be at the forte.
This works equally well with a dagger.
Don’t enter misura stretta without an advantage.