GrowPotion 101: Dos + Don'ts 📖 DO start with a clean, dry face and wait 1-2 min for serum to dry. DO only use one dip of serum for each brow and top lash line (a little goes a long way!). DON’T apply makeup immediately after. DON’T apply to bottom lashes (upper application has the lower covered). DON’T skip days...that’ll just delay your full, fluffy results.