Firstly, you have to log in your account. If you don't have any account, please register (directions in the link: https://sencoinex.zendesk.com/hc/en-us/articles/360020795311-How-to-register-sign-up-a-new-account- )
In the Homepage, click on Exchange button on the upper right corner.
Then, click on Wallets on the menu
Next, Click on the minus symbol in the line of the currency you want to withdraw, fill in the information needed in the appearing table then click on WITHDRAW button to complete.