Click "Create Portfolio" on the main page.

In the 1st step, "Exchange & Currency", select a stock exchange and the main currency.  Click "Next".

In the 2nd step, "Assets", select cryptocurrencies, which will be included in a portfolio. Click "Next".

In the 3rd step, "Details", enter the portfolio name. Here you also can make your portfolio public and take part in TradeBattle. Click "Next".

In the 4th step, "Confirmation", there is your portfolio summary. Click "Create Portfolio".

Having created the portfolio, you will be redirected to the "My Portfolios" section. All your portfolios are displayed here.