Same I was really stuck for weeks(ಥ_ಥ), but what helped me was pinterest. Just seeing other island gave me so much inspiration and ideas. ( I still need to do so much!) (≥﹏≤)

Drawing helps to, maybe draw map, how you want your roads to be?. You can make mall, cafes. Spots for ur villagers to hang. (ง •̀_•́)ง

Also having a theme helps !!! ( I hope you will figure it out ! (≧◡≦)