Adding a Texture from Photoshop
Maya 8.0 Tutorial
How to Add a Photoshop psd Texture in Maya
Texture maps provide a method of creating "synthetic" geometry. Instead of modeling everything in the scene, may times objects in the back of the scene can be plane object with an image applied.
Texture maps are also helpful for adding objects such as trees, cars and skylines where a flat representation in the back of a scene works fine.
Add a square polygon plane to your scene (Create > Polygon Primitives > Plane). Using the Channel Box, rotate the plane 90 degrees along the x-axis.
In Photoshop, open a new 500 pixel x 500 pixel document. Using the filters, brushes and text create your texture image.
Save the original psd file as a backup, then save a flattened version (Layer > Flatten Image) as a JPG or TIFF file in your project's sourceimages folder. Be sure to remove all guides from this version (View > Clear Guides).
Returning to Maya, right click the plane and choose Assign New Material > Lambert.
With the shader open in the Attribute Editor, click the checker-box next to the Color slider. In the Create Render Node box, choose Normal and click the File icon.
Under the file tab in the Attribute Editor, click the folder next to the Image Name section. Navigate to the sourceimages folder and choose the texture file. Render your image.