If you're building from scratch, Cubase or similar software allows you to layer "Lego blocks" of sound to find the right direction.
Create singable melodies on the guitar or synth. Even without lyrics, a strong motif gives the listener something to hold onto. Rusty Nail - Instrumental
Use tools like LANDR or PhonicMind to isolate the backing tracks from the vocals. If you're building from scratch, Cubase or similar