Choose a domain name that people can remember easily, and matches with the type of website you have developed. For e.g. if it's personal portfolio website you can choose a domain name with .name or .me extension; if it's business go with "title.com" etc. Make sure it's easier for people to remember.
Depending on the traffic you are expecting to your website, choose a reliable host. The last thing you would want from your website is users bouncing off from your website due to slow page load times or errors such as server down or bandwidth exceeded.
The technology you will be using to develop your website be it Ruby on Rails or Python or any other framework. This ultimately depends on your business and your requirements i.e. if it's just a simple blog or say it is an e-commerce website. You can go with say Wordpress for your blog, or if it's an e-commerce website then you might consider a Rails backend because of availability of open source e-commerce frameworks such as Spreecommerce or you could just use something like Shopify which is even simpler.
Every website has a definite purpose. It should be clear in your head what exactly is your website for. Is it business corporate or an e-commerce or a blog etc.
5. Layout and Color:
Chose the right layout and color for your website. Every website has its requirements, i.e. website's with a lot of text(say a blog) the black color is generally preferred and the layout is such that it enhances text readability. Websites with a lot of videos or photos would prefer a different layout.
6. Site Map:
A site map is a file where you can list the web pages of your site to tell Google and other search engines about the organization of your site content. Search engine web crawlers like Googlebot read this file to more intelligently crawl your site.
Also, your sitemap can provide valuable metadata associated with the pages you list in that sitemap: Metadata is information about a web page, such as when the page was last updated, how often the page is changed, and the importance of the page relative to other URLs on the site.
You can learn more about sitemaps at the Google Webmasters Forum.
You must have already read it somewhere that content is the king. Your website has to provide good and informative content to the users. Make sure you have something valuable to give to the users and the community.
You should know who your audience is and then build your content accordingly.
You shouldn't put unnecessary advertisement on your website. Make sure the ads are not blocking your content and don't look like a nuisance to your audience.
10. Pop-Up Messages:
Try to avoid Pop-Up messages. It is a terible experience for the users when they are constantly bombarded with pop up messages. It is annoying. Here is an article on Why Pop Up Ads May Harm Your Search Engine Rankings. Harming your searching engine rankings is equivalent to harming your business.
11. Attractive Design:
Should be simple, yet professional.
Use eye-catching and Call To Action buttons such as "Get Free PDF" or "Get Instant Access". Try using bright colors.
You can choose a background depending on the type of your website. Say for e.g. if it's text oriented, then choose a light background.
Images create a lasting impression, choose them carefully. Images should be of decent quality and must add some value to the content. Images make your content interesting. You can also include infographics or YouTube videos wherever necessary.
15. Easy Navigation:
Users must be easily able to navigate through your website and should be able to search what they are looking for. Create a clear navigation system, which is easy to understand, and also includes links to pages like About, FAQs, Contact etc.
There are so many websites out there, but you have to make sure you stand out from the crowd. Google also loves content which is unique, and it's gonna rank you high in search results if such is the case.
Kepp your content fresh and up to date. Try to post content at-least a few times a week. It will help your SEO and keep your audience engaged and always anticipating for more. Make sure you update the posts/articles which were written months ago, as some links might get broken, or some images which you had referred to might have been taken down.
A good website is search engine friendly. It should be easy to find your website in the search results. Make sure you adhere to search engines policies, and do not face any penalty from search engines. For e.g Using Pop Up Ads May Lead to Google Penalty.
19. Cross Browser:
A good website is one which is functions properly in most modern browsers such as Google Chrome, Mozilla, Firefox, Android WebView, Safari, etc.
20. Screen Resolution:
Make sure your design is responsive and renders the content according to different screen sizes and resolutions.
Chose your typography properly. A legible font is important. You don't want your audience to squint their eyes when reading text on your website.
If you need users to register for your website, then include some incentives or giveaways or something useful. People don't give away their emails just like that. There should be something to their advantage when they register.
23. Social Media:
Make sure you include links to your social media profiles in your site's header or footer. Make sure you add social media sharing buttons on articles or blog posts so that it is simple and easy for your audience to share your content. Use social media to your advantage as it can be a great traffic source. To learn more about how you can leverage social media to your advantage you can through this amazing post On How to Get Free Traffic from Social Media (23 Different Ways)
24. Tracking and Analytics:
Make sure you are tracking everything. Google Analytics is probably the best solution for tracking and then making analytical decisions for your website.
Make sure users feel secure while browsing your website. Make sure you implemented the necessary security features such SSL especially when users have to make a payment on your website or any other sensitive information is involved.
26. About US & Contact Pages:
Make sure you have About Us and Contact Us Pages on your website. It adds trust to your website, and it is highly recommended by Google.
A footer may not be the main thing in your site, but make sure you impress your visitors with it. Make sure it contains information about your website, and Links to important pages such Contact or About.