Suggest me Seo Off Page techniques for E commercewebsite

Promote your product category using web 2.0 or blogging. Do content marketing is the best way as per the latest SEO trend 2015. To increase users for your e commerce website do social media optimization and do branding.

Try to forums posting and question and answer site where you get do follow links.

First you need to educate yourself about SEO, and unlearn the BS you've apparently "learned" somewhere. Then do something worthwhile.

You listed all the typical crap tactics. Directories, "web 2.0 sites", and possibly press releases can get you some results if you know what you're doing. The rest is garbage, and I don't think you even know how to use those few that may work.

For e-commerce website. Mainly concentrate on Social Media.. Create good engaging content and publish it on social media. Coming to off page.. Try doing content marketing, market your content wherever possible like, different article submission sites.

You can use Quora for Q & A
Participate in Business Reviews, Communities and Groups
Infographic

Quick "wins"

1) Create a coupon code and submit to coupon code sites. Last week we received 6 signups via retailmenot.com as reported internally and through G.A.

2) Optimize your site for local. Make sure you use Google My Business and optimize your site for your local area. Be consistent when adding your site to local listing directories. You need to keep Name, Address and Phone # (NAP) written the same.

3) Give testimonials (and get a link). I'm sure you use different services to run your business. Check out their website and see if they list their customers and link to their site. If they do, write a testimonial that knocks the rest out of the water and get a link back to your site. Ex: iDevAffiliate - Affiliate Tracking Software - Affiliate Program Software

Long-term

4) Create an epic piece of content. You need a long term asset that you can use to consistently pull in links. It needs to be something that people WANT to link to. It can be a massive list (that is better than anything else you see out there), a tool, free resource or something similar.

Ex: Bitcoin History: The Complete History of Bitcoin [Timeline] - I create that site when there really wasn't anything out there. It is embedded / linked to on Mashable, Lifehacker and Stanford.

5) Blog consistently. Start with keyword research. Use Google Keyword Planner and other tools like soovle.com and ubersuggest.com to come up with keyword suggestions. Combine these into a spreadsheet and sort by search volume. Use Coshedule's Headline Analyzer and Buzzsumo to analyze content. Create headlines for mapped to each keyword. Write your ass off, publish and promote your content. Be sure to link back to each post and go back to the older posts and update links as well.

6) Give something away. I'm a big fan of Rafflecopter. I use them for giveaways all the time to get continuous social traffic and mentions. You can edit the entries to match your goals. Ask people to blog about your company for the most entries.

7) Find people that do roundup posts. Roundup posts happen all the time. I don't know your industry, but what you can do is identify sites that do roundup posts from within your niche and ask them to include you in their next roundup. Just make sure you have some cool content to share.

Social media promotion on fcaebook, Pinterest, can help to drive a lot of trafficon yoursite.

For e-commerce, social media is a great platform and coming to the off-page activity quality content submission and blog posting is good for e-commerce.

Well you just don't do those things for the sake of having backlinks. You just don't say that you've done this and that, the important thing is that you have to make sure that the websites you're working on for gaining backlinks should be relatively relevant on your money site. Please remember that.

I think you can try Directory submission and Guest posting. Directory submission is best way of Google indexing.

Off page activities for E commerce website are as follow:
Ebook distribution

Press release and news submission

Image and infograph distribution or link building through image submissions/bookmarking

Submit Product Feeds to Product Comparison/Review Sites and Shopping Engines

Branding through community participation

Sponsor or organize contests

maybe free business cards? vistprint?