Syrup
Making syrup is very easy but there are some things to think about. To begin with, it is something that is good to prepare for a while before allowing it to cool until you do the drinks. It is perfectly acceptable to pour the bottle as it has a very long shelf life, especially if you store it in the fridge.
Syrup is made of only two ingredients, Water and sugar.
I use 2/3 sugar 1/3 Water. So for every cup of water, it is two cups of sugar. Then I boil it on the stove in a pot thoroughly disqualified, to conclude, if I'm going to drop up to bottle and have to later, strain it through a fine sieve, for example a tea strainer.