GU vs GN - still fuzzy after reading the manual twice

IMS DB training. I can parrot "GU is get unique, GN is get next" but when I write the call sequence I second-guess myself.

For "read this customer by key, then walk their orders" is it GU on cust then GN on order with the right SSA parents? Or am I inventing that?

That is the usual pattern. GU with a qualified SSA on the customer. Then GN (or GNP) under that parent for the orders. Watch your SSA qualifications or you will GN yourself into the next customer.

Draw the hierarchy on paper once. GU positions. GN moves forward. GHU/GHN if you plan to update.

Paper sketch helped more than the manual. Thanks.