A better way? to keep RTV usable.

From experience or mine at least it seems the cap never gets put on right because the threads get filled with Gunk which dries up pretty fast so mainly it's putting the cap on straight and tight.. and the rest of the thing curing up inside is due to the classic bending and folding like a toothpaste tube imo... so if we can avoid doing that , chances are a tube of rtv will last its contents till actually used up.
Jmo