There is not a big or hard process to refilling the cartridge. It is the simple process.
First you have remove cartridge from the printing machine and add your ink or toner in the cartridge and again set it to the printing machine...
Check one or two sample of it and then print the paper you want to print because is there any dust or ink is mushy then original document keep as it is.
I use the needham ink's printing ink for my printing machine. It is very good for the printing ink.