The hardner for this stuff is a paste and its guesstimation as to how much you use. The first time I used it (the first time I'd fiberglassed) it didn't dry in places, so that project stopped right there.
But the second time I fiberglassed I made a mould for my mando lids (plug was from WoF plans) and I left it to cure in my utility room while the dryer was on, that cured fine.
JangoJack this is the way I used the david stuff and it worked fine for a mould and 2 helmet pulls from that mould (that was in December). It's probably not the proper/best way but for somone that had never done anything like this before I'm happy with my results from the same product.
Get yourself down to the 99p shop and get some disposable pint pots so you can see the resin mix and grab extra stiring sticks from McD's or the coffee shop to do the mixing