This construction video shows some useful construction tips on how to blend concrete with use of a mixer machine

At first put water and then required quantities of rocks and wait for 30/60 seconds, then put sands and again wait for 30/60 seconds, then put cement and finally water (0, 3L).
Cement CEM || 32, 5R
Sand 0 mm/5 mm
Rock/Pebbles – 5mm /15 mm
Concrete Mixer – 125L
Wheelbarrow – 90L
Seals – 10L