Like others have said here, I start with lot less lid charcoal. I use my Smoke Thermo to monitor temp at a cooking grate level and adjusting vents as needed to bring up to desired temp. Much harder to snuff out and bring the temp down which I do not like doing anyways as I think it creates dirty smoke. Small vent adjustment to bring temp down is fine, but I normally won't touch it, even if bit higher, as long as the temp is stable. For example, temp has come up steadily to a desired temp of 250f but has stabilized at 275f. I would just let it ride without touching vents. It should go for many hrs without temp fluctuation.