The bus passes through Sosua about 7am. Has Puerto Plata-Sosua sign on front. Flag it down. Leaves Samana at 2 pm and gets to Sosua about 5:30. 7 days a week. Bus may not always be purple. I saw a white bus the other day, don't know if this is as permanet change or something temporary. But whatever the color, it will have the sign on front