So you want to know some soloing skills. Here are 5 things that I practice daily in order to try and gain skills.
Speed. Everyone knows that speed isn't everything, but it is if you want to grow as a player. Set a metronome at a tempo that you feel comfortable with, whether it be 60 or 200 bpm. Practice scale runs, triplets, or quadreplets (IDK). Practice at a speed which pushes your boundaries, and practice daily. don't say "I can't Do Tha", because I'm sure at a point in Malmsteen or Gilberts life, they said that they couldn't do it either.
Accuracy. Don't rush it if you can't play a passage. Go through every note slowly until you have them ingrained into your visual and muscle memory. Find a song or scale that you want to practice, and go through it slowly. Learn The Song Before You Play It. Its that simple, don't rush anything, because speed does not overpower accuracy. Any musician can see difference between a guy that says that he can shred, and a guy that can.
Phrasing. This is a huge part of soloing. Many metal songs use the same scales, but why do they sound different? Timing, tempo, phrasing, etc. Pick a solo or scale that you are learning. Then use different timings during your practice time. Don't just play the same thing over again and again. You can play 2 notes over and over again at a slower than faster tempo, and make it sound better than Axe man playing "Hanger 18". Its about the musicians feel. Also, if I am learning a solo, like TBDM "I Will Return", I will try to learn it note for note. However, I also fool around and write my own fills in between. There is nothing wrong with jamming to a track that you have learned.
Fingering Patterns. Pick 4 notes. Play them in a different sequence over and over again. This will gain speed, but also stretch your fingers. Many classical pieces will have basically the same melodic line, but the only note changing is the bass. Work on fingering patterns that you have not done before. A lot of times you can find awesome melodic lines when you are not trying to stick to a particular scale but fooling around.
Sweeping. Everyones worst nightmare is sweeping. It took me almost 2 years to learn how to sweep accurately with speed. It is not a quick process, but a simple one. Start on 3 string major and minor sweeps, and than graduate to 4, 5, and 6 string sweeps. Start slow like I said before, and look up tabs for artists that you like. Than learn their sweeping patterns. Almost all sweeps are actually the same finger patterns, just different sequences or notes and runs.
I am not a music theory major or anything like that, but if you practice these skills daily than you will shred the guitar one day.
Songs I Recommend:
Born Of Osiris- "Follow The Signs"
Protest The Hero- "Sequoia Throne"
The Human Abstract- "Faust"