How can I speed up the building of farms while booming?

So, while booming I usually waste a lot of time building farms.

This is how I do:

1. Select a single villager
2. Double shortcut to select the farm
3. Click on terrain
4. Repeat

I tried to speed up this project by selecting multiple villagers (let's say 4 villagers) and building the same amount of farms (let's say 4) but doing this, when I check later on, there is always someone in idle status.

How do I avoid idle villagers while building multiple farms? Should I place the farms adjacent to avoid this problem? Any suggestion about how to speed up this process guys? Thank you!