GW ink, what is the right mix

[lambobolt]

So for all you painting studs, what is the right mix of GW ink and water? Lucas is starting to paint his tomb kings, and i wanted to teach him to ink his skellies (seeing how i did mine several years ago and drybrushed every darn one of them since i dont know about inks at the time....). but the new GW inks are much more potent than the ones i have (whcih are several years old now). so just wanted to know what most of you use as a mix of ink to water to do things like skellies, horns, etc
thanks in advance for the help