FWIW, Kodak's instructions for HC110 now include both approaches - either using an intermediate stock solution or mixing straight from concentrate.

If you want to prepare the intermediate stock solution, you make it up by adding three parts water to one part concentrate - typically those who work that way just dump the 16 ounce bottle of concentrate into a half gallon (64 US oz) container and fill it with water. When you dilute that half gallon to working ("B") strength it makes 4 US gallons of working solution - perfect for a high capacity lab.

For those of us who process a smaller quantity of film, the intermediate stock solution is a way to make the measurements easier, but the stock solution has a limited shelf life. So most of us mix it straight from concentrate. That sticky concentrate isn't easy to measure in small amounts (typically 6 ml or so for me) but solutions like small syringes help.

I find using a 45 ml graduated cylinder works for me. I put in 20 ml or so of water, then I carefully pour the concentrate in until the total volume is 6 ml more.

I've switched over to using HC110 replenished, but prior to my switch I was using as recommended by Jason Brunner - his 1 + 49 method (essentially the same as dilution "E") works well with the Patterson tanks. Here is the link: http://www.jasonbrunner.com/hc110.html

EDIT: for clarity, all the posts in this thread are assuming you are using the more common packaging that originates n North America. There is a more dilute version of HC110 that can be found sometimes in Europe.
EDIT2: Here is the link to Kodak' HC110 technical publication J24: http://www.kodak.com/global/en/profe...bs/j24/j24.pdf