You should check if your mobile authenticator is active right now. If it is not active, you should activate it using this instruction or contact technical support. If it is active, you should just wait for 7 days in order to trade your skins. In other cases, you should check this Steam support article Why can't I trade. However, you always will be able to buy and withdraw skins from our bots using real money.
You don’t need Steam Guard to buy items, so you can do it right now. Our prices are lower than in Steam. Also you will have a 30% bonus on your first payment now.