To set up your Exotel Account, the first step is to get an ExoPhone; given below is the 4 step process to acquire one (remember you would need ₹ 500 or more in your account to get an ExoPhone)

Step 1: Click on the ExoPhones tab in your Exotel Account

Step 2: Click on New ExoPhone button

Step 3: Select your region and choose the ExoPhone

Step 4: Click on Rent and then assign the desired call flow

And you are set to go :)

Video reference attached.