Creating basic PDF documents in OS X can be done through the print dialog box by using the menu titled PDF, provided the program you're using makes use of Apple's built-in print services. With this menu you can among other options save, fax, or e-mail a document as a PDF. This is convenient for the creation of PDFs, but in addition you can use both it and Preview, Apple's default PDF handling program, to further manage and refine any PDF documents you create.
Sometimes when managing PDF documents you may want to save only a subset of pages instead of the whole PDF. For instance, if a PDF has a title and contents page, you may wish to remove these, or when browsing the Web you may wish to save only the page containing a paragraph or phrase of interest.
These options can be done in two ways: The first is to specifically create a PDF containing the items of interest, and the other is to save the entire page as a PDF and then edit or extract the content you want after it has been created.
Creating the PDF
If you have some Web content or other non-PDF content that you want to save as a single PDF file, then use the print dialog to customize the PDF. You can do this by setting the page range and other print options that are available for the program you are printing from, and when you create the PDF it will be limited to the page range you have designated.
By default the print-to-PDF option will use a standard 8.5x11 format, but you can change this to better hold the content that you are trying to save, especially if you have no need to create hard copies of the PDF you are creating. In the print dialog box, select an extended paper size or even define your own and make it large enough to accommodate the items you are printing. Unfortunately there is no way to quickly resize a print canvas by dragging it, but you can preview how your content will be laid out on the canvas and adjust its size according to your needs. This option may be exceptionally useful, for example, if you want to preserve Web footer information on a single page that for some reason commonly gets wrapped to a second page.
Another thing to keep in mind is that even with custom paper sizes, if do you want to print the document in the future then the system can fit the current document to print in any paper size, so if you have slightly expanded your paper size to fit content on a single page, when you print this PDF then you can have the content scale down to both preserve its layout and show on a single 8.5x11 document.
Editing a PDF
While the option to print to PDF can be used to isolate pages (even from existing PDF documents) another method of doing this is to use Apple's Preview application. Open the PDF in Preview (or when printing to PDF just use the "Open PDF in Preview" option) and the Preview application will display it.
From within Preview, you can select pages and then drag them to the Desktop to create a PDF containing only those pages. This is convenient because unlike printing to PDF which can only isolate sequences of pages, in Preview you can deselect a page within a selection and have the new PDF contain the rest. For instance, if you have a five-page PDF and wish to extract all but page 4 to a new PDF, then you can select all except for page 4 and drag them to the desktop. The new PDF you create in this manner will be a four-page PDF containing the original pages 1, 2, 3, and 5.
These edits in Preview are done using the sidebar, so show the sidebar and from here you can Shift-click or Command-click documents to add or remove them to or from your selection before finally dragging the ones you want to the desktop to create a new PDF.
In addition to specifying the pages to include in a new PDF, you can use the sidebar to reorganize these pages by dragging them around.
Overall Preview has a number of editing options for PDFs that you can explore, but these are some that can be used to quickly isolate and organize content that you would like to preserve in a PDF document.