Here is a temp tower we like to use. Here is how to add the layer changes in Cura. Check out the discord link for Prusa Slicer users.
Adding post processing to print the tower. -In Cura be sure to set your Printing Temperature (under Material) to 265 (PETG) -Then on the top left click Extensions>Post Processing>Modify G-code -This will allow you change the temps as it gets printed. -Click on Add a script>ChangeAtZ -Do that 10 times -Change Height to [5.0] mm -Leave Apply to Target Layer + Subsequent Layers. -Select Change Extruder 1 Temp. Drop down comes up -Extruder 1 Temp 260 -Do this for all of them.
PETG 5.0 = 260 10.0 = 255 15.0 = 250 20.0 = 245 25.0 = 240 30.0 = 235 35.0 = 230 40.0 = 225 45.0 = 220 50.0 = 215
If you need any assistance please feel free to reach out to us in our discord.