Hi all! Need help with Mixxx for Techno! (No controller & Beginner)

Really getting into techno recently and really want to try mixing. I’ve been able to transition some songs into other, creating some interesting sounds and crossfades. However, I’m struggling a bit with figuring out how to lineup a few songs with different pitches. I hear techno dj’s flawlessly do it without making the pitches sound awful. I have tried to use the pitch adjustments, but again nothing sounds quite right. Should I look at songs with very similar pitches and/or bpm to ensure it doesn’t sound wrong?

Any other advice for beginners would be appreciated, I love music, but no background in production, music theory or mixing. All I know is I love music and all the different intricate details that are added. Thank you!