Also, I am going to assume you have automatic batteries?
If you have automatic batteries it will probably take some practice to get it working good.
Stand in front of a mirror and watch the LED as you take drags.
You want to see how hard you need to draw on it to get that LED lit.
And you want to see how hard you need to draw on it to keep it lit as long as possible.
For some automatic batteries your only choice is to do consecutive short drags.
And it is often said that a quick short initial draw (primer puff) followed by a real drag will work well.
Most people recommend slower, longer draws.
I recommend getting a manual battery.