Usually I start by deviding my town into sections. Then I think what I want in each section. Maybe a flower garden here, a fountain over here, and a bush shaped heart by retail. I don't know random stuff but yeah. That seems to work for me!~
Start by determining where the main roads will be. To and from the places where you go most often, so that it's practical.
You can mark them with blank patterns or flowers. I suggest making them 2 patterns large. Then figure out where you want all your smaller, secondary paths to be, and mark them the same way.
Once you have all your paths down and made in a practical way it will be much easier to work around them.