You should occasionally apply a drop of thinners to a can of this product because as you slowly use it up over a period of months it tends to get a little thicker . Apply it on too thick will ruin models .
One tip I learned many ,many years ago, was to store the tin upside down. This means that when a skin forms over the top of an oil based paint, it is at the bottom of the tin. When you turn it over to use you have a nice skin free surface to dip into. Of course, if you forget to put the lid on properly it will be a total disaster, but the plus side is that it makes you remember to put the lid on properly in the first place.