The Yetzer Hara is stronger than us. We have no hope of beating him alone. After all, he was created by Hashem, so it's like trying to fight Hashem himself! The only way we can win him over is when Hashem himself steps in to fight for us. But how do we get Hashem to do this for us?
I saw a beautiful piece in the Sefer "Shamati" from the Ba'al Hasulam that sheds light on this great question. David Hamelech writes in Tehillim, "Ohavei Hashem sinu Ra, shomer nafshos chasidav miyad reshayim yatzeileim" - "Those who love Hashem hate evil, He guards the souls of his righteous, from the hand of the Reshayim he saves them". The Ba'al Hasulam explains that "evil" refers to the Ratzon Lekabel which is "the desire to receive" that was implanted in every person by Hashem so that he can ultimately bestow all his good upon us. However, it is this very Ratzon Lekabel that separates us from Hashem, since it makes us 'wanters" and "takers", while Hashem is the very opposite of that, he only wants to "give". Just like two people who like opposite things can't be friends, and conversely, two people who like exactly the same things, become very close. Therefore, explains the Ba'al Hasulam, true Deveikus with Hashem can only be achieved when a person breaks his Ratzon Lekabel and insists that he wants to be like Hashem. This means not to be a "taker" but only to be a "giver", to give of himself to others, and to give Hashem Nachas Ruach.
The problem is, no one can break the Ratzon Lekabel. It is the very nature of our existence and it was put in place by Hashem himself. How can one break his very nature? So the Pasuk reveals to us the secret. "Those who love Hashem", says the Pasuk, "Hate evil". Hashem doesn't ask of us to break the Yetzer Hara, he asks us only to HATE IT. When we recognize how this Ratzon Lekabel has been the cause of every misfortune and evil that has ever befallen a man, we begin to HATE IT. When we realize that it is only the Ratzon Lekabel that separates between us and Hashem - like a stone wall, we begin to HATE IT. And when we finally hate the Ratzon Lekabel with a passion, the Pasuk continues: "He guards the souls of his righteous, from the hands of the evil ones he saves them".
How deep and profound this is! Hashem is not asking us to break our nature. He is not asking us to be mighty-super men and conquer a huge Yetzer Hara. Instead, he asks us only to Hate the Menuval. To hate him for being the one thing that separates us from Hashem. To hate him for being the source of all misery and suffering in the world, since the time of creation. And when we hate him with a passion and cry out to Hashem, Hashem steps in and "from the hands of the evil ones he saves them".
So Yidden! That's the secret. The more we hate that which seperates us from Hashem, the easier it gets. Take this and RUN WITH IT.