Is there a way to make a custom device for SmartThings that i can turn on and off?
I Would like to have my own custom device that i can detect when it is turned on with IFTTT, and turn the actual device on through that.
I would recommend taking a look at the Smart Apps section for Virtual Devices created in Smartthings.
Re-Linking your Smarttings Application to your IFTTT Account after you have created the Virtual Switch you should be able to see and set the virtual device that you have created as the IF triggers for on/off functions, and the device that you have power cycle functions with on IFTTT to be the action. You would create two in the IFTTT app, one for on and one for off.
I hope this message finds you well!