Often I see producers make a drum pattern and either
- keep it the same and never change it (boring)
- not sure what else to add
Here's 3 ways to add to your drum pattern. You can do this for interest or to indicate changes in song structure (hook, bridge, outro, etc).
Full video below, but here's the synopsis:
Add more of the same sound
Take your drum pattern and add in more of an existing sound. You probably have a kick and snare. Start with those.
Add in a few more kicks. Or add in a few more snares. You don't have to do both, choose one and start there.
Only add in a few more hits, you don't have to go overboard with it.
Introduce a new sound
Take a sound you don't have and introduce it. If you don't have a closed HH for example, add that it. You can use a pretty standard pattern as it'll definitely stand out if you don't have one to begin with.
Create an alternate pattern
Use the first two concepts and create an alternate pattern. Add in a few more of an existing sound you have and then add in a new sound. Build around your existing pattern to create an alternate pattern.
Video Breakdown
A breakdown of this concept is here: