Loading print cartridge?

I'm trying to load a print cartridge into my hp officejet 4215 all in one printer and its impossible!! i feel so stupid trying to put this in. any tips?Loading print cartridge?
Here is the PDF manual for your printer%26gt;





http://h10032.www1.hp.com/ctg/Manual/c00鈥?/a>





Change the ink cartridges on page 92.Loading print cartridge?
While the printer is on and plugged in, open the flap on the far right hand side of the printer.





The cartridge cradle will slide over.





If you have a cartridge in there, gently push down on the end of the cartridge and slide it out.





To install - remove any clips or tape as per the manufacturer instructions.





There is a guide in the cartridges cradle; the edges of the top lid will fit very nicely in there, it will go in on an angle.





Slide the cartridge in, gently push up unit it clicks.





Then you will need to align the cartridge (the software will walk you through the process)