Go under the File menu, under Automate, and choose Contact Sheet II. This brings up the Contact Sheet II dialog, where you can choose how you want your contact sheet to look. In the Source Images section, at the top, from the Use pop-up menu, choose if you want to open a folder of images, use images that are already open in Photoshop, or bring over photos from Bridge. In the Document section, choose the size of your contact sheet (this part is kind of like the New document dialog), and then in the Thumbnails section, choose how many rows and how many columns you want. To have your thumbnails automatically spaced, turn on the Use Auto-Spacing checkbox (or you can enter your own settings in the fields below for how you want your thumbnails spaced). If you want to use filenames as captions, at the very bottom of this dialog, you can choose to display those beneath the images by turning on the Font checkbox, and you also get to choose the size and font. When you’re done making all those choices, click the OK button and it builds your contact sheet for you automatically.
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