William Hunt, considered as a photo mosaic guru presents these simple principles that are essential to creating good photo mosaics:

(1) The large image MUST look good without too much jaggedness or color distortion. To achieve this use more and smaller tiles, use duplicates, modify tile images or add another photo collection. (2) The small tile images should be sufficiently large to view comfortably in renderings final form. If this is a display on a computer monitor or a 8x10 print, you will need to use as few tiles as possible and still satisfy rule(1). If it is a poster size printout you can get by with over a thousand tiles. (3) If duplicate use of small tiles is needed, they must not be placed near to each other. (4) If small tile images need to be modified to achieve 1-3, it should be as little as possible. (5) The target image and small tile pictures should as much as possible have some coherent theme or connection.

If you want to preview your work, use viewing options like pan camera. There is also trackball that is used to move 3D render around from different angles.

For 3D shapes, create first new layer. Fill it with color. On 3D shapes layer, create some drop shadows or darker shades of color fills. And because 3D transform only distorts pixels, you might need these fills to see effect.

If you want to create 3D effects on your text, use different transform functions. You can use shortcut key Alt + E/F and then hold down Ctrl as you drag any of handles to any desired direction.

Before you add filters or layers effect, you might want to rasterize your text layer. To do this, right click on layer in layers palette. Then, choose Rasterize Layer. You will notice that your text will be converted into a normal layer so that you can freely edit it. Create a backup copy because you cannot edit text after rasterization.

Experiment on images. There are a lot of ways in which you can create 3D shapes, objects and text.