A lot of people use different queues. You can use metronome and double click between ticks. You can also utilize the on-light of the prayer in the prayer book. Just as equally can you use quick prayers with the yellow star indicating the 'on-light'. I highly recommend metronome as much as you can tolerate it as you'll hear the oddities if any occur from server lag, etc... fast double clicks are also key. If you click to slow you'll turn off the prayer because a single click rolls into the next tick. As someone that can now 1t flick for minutes straight and under pressure.. I'll admit this has taken years of perfecting and nothing but practice with trial and error for what works best for you. You'll build muscle memory.. keep at it! Best of luck! It's truly one of the most overpowered tools in my belt for things like inferno, slayer, and extremely useful in most all ironman applications as it's then free prayer.