JJ696.
Flying jets is easier if you are in control of the a/c and ahead of it, rather than letting it fly you and chasing it. When making pitch & power adjustments it is easier to do so +/- a datum using small changes. Thus, knowing dautms and setting them to achieve a given task helps a great deal. You are giving energy to the a/c and asking it to behave as you would want. If you give it the correct amount of energy (datum), and see how it is feeling today, you have a chance of coaxing it into submission, gently. A little more or less, or even find you have chosen correctly, will win the day. Guessing in the dark and pumping the thrust levers is handing control to the a/c and will bring you a troublesome workload. Fly the automatics and watch what they do. The next time you want to do the same thing manually, copy the auto-settings. B737 for level flight in the circuit 6 & 60% works as a starting datum. More drag will require a little more thrust. On finals, trying to keep things simpel and easy to remember I use F30 = 53% F40 = 64% F15 SE = 75%. There are 3's & 3's, 4's & 4's & 5's & 5's. If level on SE add 10% to the 2 engine settings. On finals these numbers work for headwinds of 10kts and normal landing weights. It will take quite a few tonnes to changes these by much, but greater changes are needed for wind effect. i.e. higher Vfly for head wind will need more N1% than a couple of extra tonnes. Tailwinds will require less. This also allows you to sense the wind when noticing the required N1%.
If you set these datums in advance, and watch the a/c's behaviour, then make small adjustments to find 'today's' datum you will be controlling the a/c and not the other way round. Chasing the speed down finals is hard work and not recommended.