The disposition will depend on the format of the document and the number of pictures that you wish to insert in the layout. It is always necessary to think about the harmony of the whole set.
In the case where the layout contains one picture, there is no problem. When you put there several pictures, the disposition is important and the success of the whole set depends on it.
It is good to ask yourself some questions. Do you wish to show off one picture or you are going to present them in a uniform manner? Do you add texts? Do you include decorative elements? This will allow you to choose well the positioning and picture shapes for cutting.
The two following examples show two different presentations and two different showings-off of the pictures.
For this layout, the idea is to show some pictures from a travel without prioritizing one among them. Thus, the pictures have the same size and presented at the same level.
In this layout of the family photos, the people are highlighted compared to the size of the picture. The other smaller pictures are put here for decoration.
Instead of positioning pictures as you do it in a simple album, you can nest the pictures. This creates a coherent set.
The nestings may be created with all the shapes. They are particularly successful with oval picture shapes.