going down
The oldest and I think the simplest way to reflect the forces in a turn is to draw a parallelogram showing the the reduction in the vertical component of the lift force and an increase in total weight.
As bank is increased the load (centrifugal force) adds to weight (total weight) - the aircraft becomes heavier, while the lift (centripetal force) becomes increasingly a turning force with therefore a reducing vertical effect. Unless lift is increased and the vertical component (total lift) balances total weight the aircraft will descend. As bank is increased the aeroplane descends more steeply.
You should also include in your brief other factors such as; increase in the stalling speed ( the parallelogram will help explain) and the changes of attack of the inner and outer wings in the descent. This difference of wing incidence can be drawn but is more difficult and requires practice. I'm sure that you will find illustrations in most text books.