Generally I mix my epoxy in small batches using syringes. My ‘station’ is a repurposed baby changing think. Said baby is now 15 and eats tubs of beans at every meal, they come in handy.

The two compartments stop contamination and as you can see the harder lid is marked as is the syringe but out of shot. Both syringes have their own drip tubs. The middle tub is obviously where the mix goes.
It is very easy when the bottles are full but a bit tricky with partial bottles. What you don’t want is to get the outside of body the syringe covered in epoxy. By accident rather than design by moving the drip tub it is easy to tip the bottles so that is just inside the neck.

I’m working on my canoe hence the small syringes but do use bigger syringes which is better loosing count of multiple small syringe counts.