If you have a lot of coinage you can use this trick to gain experience.
Plow a bunch of plots
Plant an inexpensive crop that has XP (soybeans) (Sweet Seeds for Haiti limited time)
Dig em up
Repeat over and over.
Using a macro program
You can use a macro program to record your clicks and then repeat them over and over. There are several macro programs you can use depending on your operating system i.e Windows of Mac. Below are some good choices.