I feel a bit stupid asking this question as I have been a painter for many years but still don’t feel confident about the best way to use medium. Years ago I used Maroger and then switched to Daniel Smith’s painting medium, both gels. The latter was recently discontinued and now I am using Gamblin’s Alkkyd. I seemed to work better with the gels and have little experience with a liquid. I usually use minimal amounts. sometimes I will simply dip my brush in the medium then gently blot on a paper towel leaving just a small amount on the brush. If I have premixed puddles of paint, especially when using a stiff lead white, I may mix with a small amount of medium. I am afraid of using too much, respecting the fat over lean rule, and also because years ago I made quite a good painting but unfortunately the surface, after using medium, became too slick to support additional paint.
Any thoughts?
What a great question Sandra. I believe that many artists spend a good portion of their career trying to find the perfect medium relative to their efforts. You seem to use your medium exactly as I do–sparingly and for very specific (pragmatic) tasks. I continue to use Maroger but not the sticky Flemish version-the Italian Version. It is gel-like when exiting the tube and becomes more “liquid-like” when agitated (thixotropic). It has wax instead of the mastic and turp found in the Flemish version:
http://www.oldmastersmaroger.com/italian-wax-painting-medium/
You might want to give it a try!
I loved Maroger medium but stopped using it only because of a painter, in a neighboring studio, who complained about the odor. (Flemish kind) I am now in a new building and therefore realize I can return to my beloved Maroger. I will certainly try the Italian. I just watched a couple of very helpful videos, on the Old Masters web site, that demonstrate its use. So, thanks for reminding me of what I’ve been missing!
PS. I am getting so much out of Smartermarx, already! Thanks again. 
Again it’s my pleasure Sandra. I am very thankful for what you are contributing as well. I’m very proud of the community we have built here.
I hope you and yours have a wonderful Holiday Season and a stellar New Year! (Here’s to a 2018 filled with more great art and great conversations!) 