Simply believe, and know in your heart of their existence. Think about it. In all of this vast Creation, can you really believe that you are alone?
I will pre-warn you though, so as to avoid disappointment, you will only receive communication from them, if that is something you have already agreed together in your Soul Contract before coming here. Many here at this time (millions) have a part to play in the Great Awakening, and preparations for the Great Harvest. Many who do not believe now, will begin to open their minds, as the Earth changes that are coming begin to take effect. People will be terrified, and have no idea what is going on, because the governments have concealed this information from you. These 'Travelers' or what some have termed "Star-Seeds" are incarnated here to help on the ground level, when this all begins play out, over the next few years. When the time is right, they will come forward.
Most people are not ready to hear this information yet, but not so far off, they will be.
Many of these "Star Seeds" have not "awakened" yet themselves. The Confederation stands by ready to "help" them to do so, if it is necessary. For ones such as these who have yet to "awaken", they will have felt all their lives that they are somehow "different", and they have a deep sense that somehow, they "do not belong here". Many of them will also have many dreams and even visions, of their lives on their Home planets. Many of these "Star Seeds", are in fact Plejaren. That is why the 'tall blondes' keep 'showing up'. To help their Family awaken to their assignments here.