Hi mate. I’ve been serious at my hobby for over a year now, and to be honest, all things come with practice. I started with getting to know my library real well, looking for transition points throughout each track and setting cues. At nearly 8k songs, I ain’t nowhere near done yet, but the point is, you’re learning all the time. The best trick I’ve learnt is to cut the bass of the program track to switch attention to the track I’m mixing into. It’s simple and means you can concentrate on the transition. Next thing I now do regularly, is record every time I practice mix. You soon pick up on what you did right or not when listening back to it. Also, I’m creating simple loops on tracks to give breathing space during the transition from 1 song to another. I am sparingly using effects in my transitions, I have set my FX on both decks to Serato combo filter, echo and reverb, so I know what I have straight to hand during a mix. 1 thing Uncle Phil has suggested is to apply a sympathetic filter to a track that has been produced with it playing and it’s paying dividends for me.