There are many best practices used to increase the ecommerce conversion rate.

Since you are asking a favorite tip, my favorite one is:

Landing Page Optimization

Let's start with the definition of a landing page. Because I still observe the confusion about the actual meaning of landing pages.

What is a landing page?

Simple definition of a landing page is just what it sounds like: it’s the page your website visitors arrive at after clicking on a link. This link could be on a search result page, on your home page, on a directory or another website, or on any other page in your site (internal link).

So, after a visitor clicks a link, they land on your landing page. Whether it is your home page, a category page, your blog's home page, or a product page, it is your landing page.

How to Optimize Your Landing Page to Increase your Ecommerce Site's Conversion?

First and most important of all, your landing page should do what it tends to do. If your landing page's goal is to announce the special of the day, it should. You shouldn't confuse the visitors with other banners, and nonsense stuff. The main focus should be the special of the day.

Treating Each Product Page as a Landing Page on an Ecommerce Site

The real secret is here. Most of the ecommerce sites focus on home page and category pages. They create nice category banners, etc. and just dump the manufacturer's product descriptions and the standard manufacturer's images to the product pages, and complain about the low conversion rates.

If you have an ecommerce site, most of your visitors will come direct to your landing pages. They will come through search engines by searching long tail keywords, or they will click on links on other sites. One of your product pages is going to be the landing page, and the entry point to your site.

You have to treat every single product page as a separate landing page. Here are my tips about optimizing product pages and treating them as landing page:

• Write a unique description for each product. DO NOT use the manufacturer's product descriptions. This will not only help with better search engine rankings, it will also increase your overall conversion rates. Be as specific as you can on the product descriptions, and always keep in mind that this is your sales letter. Don't be boring, don't be too formal, or informal. You have to find the balance depending on your audience.
• Use additional product images. Everybody else has the same images supplied by the manufacturer. Be creative and use extra/different images than everybody else.
• Customer Reviews. I can't tell you how effective real customer reviews are for increasing your conversion rate. Don't moderate the negative reviews. Keep in mind that quality negative reviews left by customers will help your potential customers to make a smart purchasing decision. They will also decrease the overall return rate for your ecommerce business.

Above are just the basic tips to get started. You can do so many other cool stuff to optimize your landing pages (such as video, social content, etc.)

If you want to take your landing page optimization to next level, you have to have a multi variable testing tool. Don't settle with an A/B testing tool.

Start using Google Website Optimizer. There are more sophisticated tools out there, but Google Website Optimizer is free and it gets the job done.

Ecommerce Conversion Rate Optimization should be one of your main focuses if you want to run a successful ecommerce business.

And my favorite tip to increase your ecommerce conversion rate is Landing Page Optimization.

What are your favorite tips?

Some of my tips but not all;

More high quality product images,images from different angles, detailed product descriptions,videos are hot right now.

Customer reviews and testimonials section is another must have these days.

Social media integration is increasing your brand reputation so your conversion rates.

Easy check out system is helping less internet savvy customers.

Wish Lists or shopping list integration.

Make your customers/visitors interact with each other by integrating social widgets.

Set up a Company Blog and do not make hard sell.

Post your Coupon Codes to Coupon websites.

Deal of the week section.

My favorite tip to increase ecommerce conversion rate is having a Toll Free Number.

We've increased our conversion rates by 25% after placing a visible toll free number on every page of our ecommerce site.

Having a toll free number will definitely bring in extra cost to your business. You need to be able to have a customer service rep (or yourself) answering the calls and helping the customers.

But it definitely helps to gain trust and increase conversion rates.