Things You'll Need
Launch Adobe Illustrator by double-clicking its icon on your computer desktop or by selecting it from the "Start" menu in the lower left-hand corner of the screen.
Click "File" in the top menu bar of the Illustrator window and select "Open" from the drop-down menu.
Navigate to the Illustrator file that you wish to convert. Click on the file and press "Open." Adobe will now render the graphic file and display it in the main Illustrator window. Make any last-minute modifications to the graphics where needed.
Click "File" and select "Save As PDF."
Choose the type of PDF to which you wish to convert the Illustrator file. Adobe Illustrator allows you to convert an Illustrator file to "PDF/X-1a" or "PDF/X-3." The latter PDF format saves the Illustrator's color management information so that the PDF images display correctly. This is not an issue if you are merely exporting the Illustrator file as a PDF for preview purposes, though some clients may prefer to see the most exact replica of the graphical file as possible. Both PDF/X-1a and PDF/X-3 are compatible with the most recent versions of Adobe Acrobat Reader and Adobe Acrobat.
Set any additional PDF preferences that you may have, such as where to include the graphics as color bitmaps or grayscale bitmaps.
Click "Save As PDF" in the lower right-hand corner of the dialog box. Adobe Illustrator will then convert and export the file as a PDF