How were each of the following cations utimately separated from the rest of the group and /or decorated? The use of equations may be helpful, where applicable.

Ag+
K+
Nh4+
Al+

The question asks how you did it and I don't know that.

What does decorated mean?
Ag HCl to ppt AgCl without the others.
Add NaOH to ppt Al(OH)3 without the others.
Adding NaOH will convert the NH4Cl to NH3 and that can be expelled.
K^+ will be left.