I have a bag of shellac flakes and want to touch up my handlebars - they're already shellaced but some has worn off. I'll need a very small amount and don't want to end up with another full jar that I'll never use. So I'd like to mix up a small amount. But all info I find online is about large quantities, with formulas given in the arcane and confusing "2 pound cut" jargon, and they warn you how it won't dry, or won't last, or how the world will end if you don't mix it like Antonio Stradivari did.

Has anyone had good results mixing up small amounts without measuring?