PSA: DO NOT BUY SIMPLE SYRUP! It's the easiest thing to make, hence the name SIMPLE SYRUP. Now, that we've got the all caps bit over with, let's get on with the recipe. And even "recipe" is a bit of a stretch. Simple syrup is literally two ingredients—sugar and water.
Here's what you do:
Pour equal parts water and sugar into a saucepan. White sugar will give you a perfectly clear syrup. Raw sugar, like organic cane sugar with give you a more golden syrup.
Stir the sugar and water over medium heat until the liquid around the edge of the pan begin to simmer or until the sugar is completely dissolved and clear (not cloudy). Remove from heat.
If you wanted to add flavouring to your simple syrup, the time is now. The options are endless. Try fresh herbs like rosemary, lavender or orange peel. Vanilla bean, sliced ginger or cinnamon sticks are also popular. If you're adding a flavour, allow the syrup and flavouring to steep (covered) for a couple of hours or overnight—depends on what you're adding and how strong you want your flavouring.
Store syrup, covered and in the fridge for up to two weeks.