What is the best way to travel from Guangzhou to Chaozhou, Meizhou and then to Xiamen?

There is no high speed train between GZ and Chaozhou or Meizhou. To reach Chaozhou or Meizhou, you can find frequent buses from GZ Tianhe Bus Station.
To Chaozhou, the bus journey takes about five to five and a half hours. To Meizhou, it takes about 6 to 7 hours.
From Meizhou to Xiamen, there are two trains, spending about 8 hours. Or I heard there is only one bus at around Wuzhoucheng Bus Station.

There are two trains a day from Guangzhou to Chaozhou - travel times 7hours & 8 hours

There a numerous buses from different Guangzhou bus terminals - travel time to Chaozhou about 6 hours