Opinions differ on defining the popular fonts, that were used for the 60s designs. Thankfully, the modern creative artists found the ways to capture that groovy spirit styles any old-school font possessed. Among the free hippie fonts, you might find The Bambank Script, Bell Bottom Laser, and Goodbees. The best ones from a paid section are Surreal Psychedelic Typeface, Euphoria Party, and Janger – Display Font.