For the simple syrup and lemonade:
Make the herb-infused simple syrup: In a saucepan or pot with a lid, bring 1 cup sugar, 1 cup water, and 1 cup herbs to a boil, stirring. Immediately remove from heat, cover, and allow to steep for 10 to 30 minutes, depending on how strong of an herbal flavor you want your drink. Strain out the herbs if you like (I leave mine in the entire time for a very herbal syrup).
In a pitcher, dispenser, or something from which you can easily pour, mix the lemon juice, 4 cups of water, and 3/4 to 1 cup simple syrup. Taste for sweetness. Keeping in mind that the drink will be diluted with beer when you mix it, I tend to go a bit sweeter than I normally would with lemonade.
Add ice to the lemonade if you’re serving to many people right away; or add ice glass-by-glass for all-day-long consumption.
Fill a tall glass (with or without ice) halfway with the lemonade. Top up the rest of the glass with beer. Garnish with an herb sprig.
If you have leftover simple syrup, it will keep, in a sealed container in the fridge, for a week.