1. Move image files that you want to georeference from CDs to a local directory.
2. In the folder, select all files (ctrl+a) then right click, open “properties” to uncheck “Read-Only” attribute.
3. Use Adobe Phtoshop, and open all the image files to correct northing direction of each picture (image file). 
4. Open ArcMap. Go the “View” menu and choose “Toolbars”. Turn on the Georeference toolbar.
5. Add reference layers (roads/streets and/or hydrography) in the view. 
6. Add an image file to the data frame. At this point, the image file may not show up in the same view extent (because the image file does not have any projection information, the file will be located at somewhere else).
7. Zoom out (or use Full Extent button) so that both reference layers and the image file can be seen in the same viewframe.
8. Zoom into the section of the reference layers, where the image will belong. Usually, scale size for a typical aerial photo is somewhere between 1:40,000 and 1:10,000.
9. Go to the Georeferencing toolbar and click “Fit to Display”.
10. There are 2 tools for moving/rotating the image in relation to the Vector layer. Click on the “Shift” button (a small arrow that points to the right) to move the image to the correct location. Click the “Rotate” button (a small circular arrow) if the image appears to align better if rotated a bit.
11. The image will not be lined up perfectly at this point. You need to plot control points and stretch the image so it matches the vector more accurately. Click on the “Control Points” button (two small x’s connected with a line). Stretching goes in order from the raster to the vector. So plot the first point on the raster then click to the point on the vector that it lines up with. You need to plot at least 3 sets of control points to be able to save the image with its updated georeferenced properties. For the best results plot a control point in each of the the four corners of the image.
12. Clicking “Update Georeferencing” from the “Georeferencing” drop down list will automatically save the latest changes you’ve made to the raster. After updating, a world file (TFW for TIFF, JGW for JPEG), which contains georeferencing information, will be created. Without this world file, the image file will not be read as georeferenced file, thus must be stored with the image file. This world file is also important when exporting a map as a georeferenced image. (See more detail about TFW or world files at ArcMap help, “Exporting a map to create a georeferenced image”) 
    

Georeferencing Tips:

1. The more control points you plot, the more stretched the image will be. After about 10 sets are plotted, any subsequent sets will not make much more of a difference. Too many control points will stretch the image beyond recognition.
2. To check if the image is georeferenced or not, look for the World File (.tfw for TIFF format & .jgw for JPEG format) with the same name as the image file in the folder.

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