If your page is mobileOK Basic

and you want to compliace with WCAG 1.0 Level A

In General
1.1 Provide a text equivalent for every non-text element (e.g., via "alt", "longdesc", or in element content). This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ascii art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and video. [Partially] Test only if text alternative is meangiful
2.1 Ensure that all information conveyed with color is also available without color, for example from context or markup.
4.1 Clearly identify changes in the natural language of a document's text and any text equivalents (e.g., captions).
6.2 Ensure that equivalents for dynamic content are updated when the dynamic content changes.
7.1 Until user agents allow users to control flickering, avoid causing the screen to flicker.
14.1 Use the clearest and simplest language appropriate for a site's content.
And if you use tables
5.1 For data tables, identify row and column headers.
5.2 For data tables that have two or more logical levels of row or column headers, use markup to associate data cells and header cells.
And if you use applets and scripts (Priority 1)
6.3 Ensure that pages are usable when scripts, applets, or other programmatic objects are turned off or not supported. If this is not possible, provide equivalent information on an alternative accessible page.
And if you use multimedia (Priority 1)
1.3 Until user agents can automatically read aloud the text equivalent of a visual track, provide an auditory description of the important information of the visual track of a multimedia presentation.
1.4 For any time-based multimedia presentation (e.g., a movie or animation), synchronize equivalent alternatives (e.g., captions or auditory descriptions of the visual track) with the presentation.

to became Level AA

In General (Priority 2)
2.2 Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen. [Priority 2 for images, Priority 3 for text].
3.1 When an appropriate markup language exists, use markup rather than images to convey information.
3.3 Use style sheets to control layout and presentation.
3.5 Use header elements to convey document structure and use them according to specification.
3.6 Mark up lists and list items properly.
3.7 Mark up quotations. Do not use quotation markup for formatting effects such as indentation.
6.5 Ensure that dynamic content is accessible or provide an alternative presentation or page.
7.2 Until user agents allow users to control blinking, avoid causing content to blink (i.e., change presentation at a regular rate, such as turning on and off).
10.1 Until user agents allow users to turn off spawned windows, do not cause pop-ups or other windows to appear and do not change the current window without informing the user. [Partially]
11.1 Use W3C technologies when they are available and appropriate for a task and use the latest versions when supported.
11.2 Avoid deprecated features of W3C technologies.
12.3 Divide large blocks of information into more manageable groups where natural and appropriate.
13.1 Clearly identify the target of each link.
13.2 Provide metadata to add semantic information to pages and sites.
13.3 Provide information about the general layout of a site (e.g., a site map or table of contents).
13.4 Use navigation mechanisms in a consistent manner.
And if you use tables (Priority 2)
5.3 Do not use tables for layout unless the table makes sense when linearized. Otherwise, if the table does not make sense, provide an alternative equivalent (which may be a linearized version).
5.4 If a table is used for layout, do not use any structural markup for the purpose of visual formatting.
And if you use forms (Priority 2)
10.2 Until user agents support explicit associations between labels and form controls, for all form controls with implicitly associated labels, ensure that the label is properly positioned.
12.4 Associate labels explicitly with their controls.
And if you use applets and scripts (Priority 2)
6.4 For scripts and applets, ensure that event handlers are input device-independent.
7.3 Until user agents allow users to freeze moving content, avoid movement in pages.
8.1 Make programmatic elements such as scripts and applets directly accessible or compatible with assistive technologies [Priority 1 if functionality is important and not presented elsewhere, otherwise Priority 2.]
9.2 Ensure that any element that has its own interface can be operated in a device-independent manner.
9.3 For scripts, specify logical event handlers rather than device-dependent event handlers.