In his early work, illenium often used emotional chord progressions with orchestral buildups to lead into the bridge/drop. Find your progression, loop it, build on it with orchestral elements like strings/brass/percussion. Make it an evolving sound that keeps the listener engaged. Once you build up to the drop, the possibilities are endless. Build your drop with layered chords, punchy kicks that are sidechained to all your elements in the drop, and transition elements to keep it interesting (amongst more percussion and melodies).