I use a needle-tipped plastic 50mL bottle to dispense my nicotine for mixing. I counted the drops it takes to reach 1 mL of liquid by weight on my scale. In my case it was 66 drops per mL. It will vary based on what bottle, tip, and which base your nicotine is suspended in (eg. vegetable glycerine forms a larger drop than propylene glycol).
I'm using 100 mg PG nicotine. I divided 100 by 66 and it came out to 1.1515~ mg per drop on average. I'm sure there is some variation, but it doesn't matter much to me.
I open an altoids tin and spread the mints out in a tupperware container flat. Then I put one drop on each mint. Let it sit out overnight to fully absorb the nicotine (even though it might not be necessary, the nicotine solution looks mostly absorbed in less than an hour). The next day I put the mints away.
Your drop/mL measurements or nicotine strength may be different, or you might want a different strength of nicotine/mint. I only use one drop and it works good, not sure if more liquid would still absorb. It might be worth diluting your nicotine and trying it a lower strength, then working up from there in small increments.
The mints takes some getting used to, try not to chew them or suck on them, it works best for me to leave them under my tongue. Swallowing saliva that has too much nic in it makes me hiccup, and is a little harsh. After I got the use down right, they work great for me.
Never leave them where anyone, especially children, can access them, and always put them in a child safe container. I like the one I use because it looks ugly, very unnatractive, and is old and worn out, and it has a child lock cap on it. Also it's waterproof and small enough for me to keep in my pocket.
As always, try at your own risk, just my opinion, be safe, etc.