Step 1 (Root-Extender)
The easiest way is to start to mix up your soil with the rootextender, use 5 gram (1 pack) per single clone or seedling. Off this amount mix 3-4g in with the soil and put the remaining 1..2 near the roots. (this will be done later) And fill up your pot with soil.
Step 2 (Soiltab)
Dig a 2'' hole in the middle with your fingers and put the soiltab in.
Cover this with a bit earth and now plant your seedling as usual.
(Don't forget to add the 1..2 gram root-extender we had left earlier around and under your seedling)
Step 3 (Flowertab)
When you put your lights on 12/12 lightcycle or the plant is starting to pre-flower its time to use the flower tab.
You just push 1 tab a few inch in the soil near the roots, This will provide the plant the nutrients they need in the flower period.