The basics for any good rock guitar solos are scales. Practice scales, and you will have the best basic technique for playing (and composing/improvising) solos. There are some good answers that relates to this in this question: Why learn scales? What are they for?Why learn scales? What are they for?
About what kind of scales, and how to practice, you can find some useful answers in this question: Logical way to learn movable scales on guitar?Logical way to learn movable scales on guitar?
