I was advised this and it seems to work.
Eg, cleito .4ohm coil and its new. 40 to 60w coil.
For the first tank i set my watts low at say 40 to 43 w, after that i up it to where i find the flavour at its best and for me its around 48 to 50w. Low watts they last longer but taste isn't as full as it is up higher. Personally i dont like it above 50w for that coil but we all have dif tastes and others like em high. Experiment.