1) For each of the molecule coloured in blue(carbon atoms)
you have to find chiral/asymmetric ones(ones with all four
groups attached to it are pairwise different...
2) If the directly attached atoms are same for two or more
groups go to the next attached to these attached atoms until
you find some difference...
3) If atleast two of the attached atoms are same for any
carbon atoms than it is for sure not asymmetric...
4) If you find out some carbon atom to be chiral than click it
if it changes color than you are correct otherwise you are
wrong
5) Click it again to revert the color back to blue