It degrades at a rather quick pace in water. I wouldn't do it if you plan on storing it more than a week.
I had success eyeballing it by taking what I thought would be a good dose, then taking a quarter of that intranasally and titrating that way.
However for HR's sake I don't recommend that, many people have gotten really messed up that way, especially with foreign substances that aren't a powder and just a bunch of clumps.
As well orally this would e very impractical due to the longer come up period.
Get a scale, a Gemini-20 isn't very expensive and weighs accurately enough in this dosage range.
Many people had good lucky increasing the accuracy by removing the weighing plate before turning it on, then placing it on and using simple subtraction to find their dose, it seems to weigh better in the 25+mg region