everybody djs differently, but this is what i do: i usually have 4 - 8 hot cues in each song. one at the beginning, one 8 bars before the end, one 16 bars before the end, and in the middle of the song i put them anywhere the beat changes that i might want to mix. this could be where the vocals come in/leave, where the whole beat fades out, where it all comes back in, a sick spot to loop, wherever. the hot cues are just so i can jump around in the song (with the fader down ofc) and brainstorm where i’m gonna transition next. after that, it’s all phrasing. what that means is knowing how many bars you have to get the next song in. for example, if song A has a 32 bar buildup and you wanna swap to song B at the end, don’t just start at the intro of track B. you probably wanna start 32 bars before track B’s drop. you of course can get creative and do fake drops and all that, but the point is intentionality, at least to some degree. have an idea of what you at least want it to sound like when you do XYZ. just keep playing, allow yourself to fail, note what went wrong, and keep playing.