That instruction is for the version of Pages that works, Pages '09.
And you are not using Mavericks.
Before Yosemite it used to be possible to copy anything and create a new file in Preview .app just by going command n, but Yosemite now turns the clipboard into a low res 72dpi file, rasterising all text and vector content.
Like every thing Apple does lately, Yosemite is a huge step backwards and undoes all the good work that went into OS X in the last 15 years.
If the multiple items are all bitmap images, you can create a blank bitmap file in Preview:
1. Make a simple screen grab of a white area anywhere in view with command shift 4 > drag over area
2. Make that screen grab the size you want it to be under Tools in Preview
3. Open your original images in Preview and Copy/Paste them one by one into the blank file, positioning and resizing as you go.
4. Saving will freeze the final design as one image.
Peter