Export a PDF to these settings:

Specification: NewspaperAds_1v4_fault_truetype (by GWG)

PDF Standard: PDF/X-1a:2001

Convert to CMYK using these settings:

Profile: ISOnewspaper26v4 [download] (IFRA26 Max TAC 240)

The specifications contained in this section are for both Display (Run Of Paper) and Classified sections. Please ensure you have the right section for your ad. Sections are clearly marked.

For a list of approved repro houses, Bureaus and advertising delivery methods please see the links below:

Delivery Methods: http://www.guardian.co.uk/advertising/electronic-ad-delivery

Approved Senders: http://specle.net/uk/guardian-news-media/approved-repros-bureaus

For some general guidelines to designing your ad to make it suitable for print, please see this link: http://specle.net/uk/guardian-news-media/print-guidelines-for-guardian-observer

WE DO NOT accept emailed advertising of any type. You must use one of our approved delivery methods.

We never accept any advertising copy with crop marks, colour bars or other printers marks of any description. Advertising should be supplied to exact dimensions only.