A perfectly optimized webpage should blend content and simplicity with social media and SEO integration to ensure the user is highly engaged and the site is being crawled by search engines.
According to Search Engine Watch, this can be achieved by focusing on tags, content, video and links, to name a few items.
For instance, be sure to include title tags, header tags and descriptions when writing code for the page. These should all be relevant to the main focus of the site to encourage clicks, but be wary not to over-optimize with keywords, as this can be frowned upon by Google.
When creating a unique URL, try to incorporate a primary keyword in the web address if possible.
As for the content itself - again, don't cram in keywords as this will seem spammy to Google and ultimately hinder search engine rankings. Updated, informed content is generally the best way to go.
Alternative content such as video can help increase engagement levels and reduce bounce rates, and may also appear alongside search results. Also, if a webmaster chooses to add a news feed, he or she should make sure it's from a source that already exists and is constantly updated.
An optimized site can't be complete these days without involving social media. Its benefits, SEO-wise, are increasing due to Google's recent Search plus Your World algorithm, which integrates Google Plus recommendations into organic search results. Also, it can never hurt to share content with Google Plus' growing audience, as well as Facebook's 800 million-plus user base and everybody on the Twittersphere.
While a perfectly optimized page may not be realistic for every website because of the nature of their business, their philosophy, etc., there seems to be a general consensus among developers over how to properly optimize a webpage for mobile.
Social Media Examiner points out that due to the restricted screen space, businesses must determine which key pieces of information they'd like to share with mobile users. Keep things as simple as possible - a complicated store locator or forms with many lines to fill out may not be optimal for a mobile scenario.
And, because mobile pages tend to load slower, keep the number of pages to a minimum. Also, make proper use of white space instead of cramming tons of information onto a page, and avoid Flash - Apple products don't support it, thus negating about 30 percent of the smartphone market.