To add a new token, go to Settings on the top right corner from the main menu. Select Manage assets, if your token is listed, check the circle next to it.
If not, you will need to Add a new asset by Clicking the ⊕ icon on the top right corner. You will need the following information that can be found by searching for the required token at Ethplorer (make sure you are selecting the token you are looking for as some tokens have either similar symbols or names, although there is no risk of adding other tokens):
- Contract Address, which is the address from which the token was deployed
- Token Name
- Number of Decimals