Personally, regardless of the type of sugar I am using, I do a whole batch at a time rather than mess around with a teaspoon into each bottle.
Before I wash out the bottles, I dissolve the required amount of sugar in a small amount of water as I bring it up to the boil in a saucepan.
I cover the saucepan with tin foil and let it cool whilst I am washing the bottles and syphoning the beer into the Bottling Bucket.
As the syphoning is taking place I pour the cooled sugar syrup into the Beer Bucket and gently mix it into the beer (being careful not to get too much oxygen introduced) before starting to fill the bottles. :thumb: