Learn English – How to abbreviate a double-barrelled surname

I have the initials D S-K as I have a double-barrelled surname, and this has always been how I have written them. I was recently reading through The Lord of the Rings, and realised that a character's double-barrelled name (being Sackville-Baggins) was said to have had the initials S.-B. which made me think about abbreviations. Is it right nowadays to use both dots and a hyphon in a double surname? Even Tolkien himself uses dots to show abbreviation in J. R. R. Tolkien, but I have never used them for my name before let alone a hyphonated name.

So should my name be abbreviated as D. S.-K., D.S.K. or should I even use the dots at all? I never really see them being used in names now and never have used them myself, are they even used anymore?

Even then, I am not even quite sure if it would be JRR, J. R. R. (with spaces) or J.R.R. (without) or if they are all acceptable?

Thanks!