Once they start, they grow super fast!
After a few weeks or a month, the leaf will mature and you won't be able to see it grow anymore... It'll be growing a new bulb at that point!
The spike/leaf that's appearing will consume almost the entire bulb in the process, the bulb you bought, will literally vanish! Leaving a hole in the soil, make sure the bulb is atleast as deep as the bulb is wide, if it's 2" across, 2-3" will be fine.
Start it out in a bright spot before the spike emerges, or its permanent spot if you won't be moving it, konjac wants a lot of light, some shade from the heat of the day will be ok but mine get pretty full direct sun from sun up til 4ish
They like to stay moist!
Lots of fertilizer will be a big boost too!
It'll make a bigger bulb for next year, that in turn will make a bigger leaf....won't really help with this years growth, it's a big long cycle by most plant standards but it works...
I'll be planting mine up soon, if I have the energy I'll make a post about it.