By now, perhaps you are coming along well with the exercises. But you may wonder how on earth do you apply technique to soloing? This is a difficult question and is similar to the equally difficult question, "How do you play lead"? There are no strict answers to these types of questions. Some people prefer to learn a handful of riffs, and then their playing becomes dominated by their riffs. I prefer to view solos like vocal sections. Whether it is a solo, or a melody, I feel that something is always being communicated, and what better way to communicate than treating your guitar like a voice. So when I write solos, they usually are inspired by a melody and are dominated by the melody. A solo may have several main parts, and technique comes into the picture when I try to connect the parts meaningfully.
The exercises that follow show riffs from a few songs I recorded (some in dire need of a re-recording!). In the included audio files, you will notice that you don't hear the riff until several seconds after you start playing the file. I did this so that you can hear the musical context of the riff (i.e. what led up to it).