CE4 is non-rebuildable.
Assuming its ur first time-vaping as a beginner..u need to slowly upgrade at least to CE5 or CE6, then to Vivi Nova..
Learn how to rebuild simple Top feed clearomizers...easier for beginnners is to get NR-R-NR wires (chk my earlier posts on such wires) to protect ur rubber grommets and minimize powerloss, besides being easier to rebuild.
Then u might wish to move on to bottom feed clearomizers or BCC for more flavour at the expense of lesser throat hit...start with single coil heads, then use dual coil heads and rebuild using single coils...same effect.
Forget about cloud-chasing for time being which u dun need at this moment as there are risks.