Except SEO and Adwords, are there any other ways to make the online marketing easier and more efficient?
Seo is a very painstaking work and Adwords cost money and time at the same time.
Every method out there is going to need time for you to be able to accomplish. It's also going to take time before you'll be able to see the results that you want to see after your marketing efforts.
Anyway, to answer your question, you should try the classic methods like word-of-mouth advertising, and perhaps asking your family and friends to spread the word about your online business on their social media pages, so that it can effectively reach your deep-degree networks.
I hate to be rude, but there is a whole field related to this that many people get whole degrees, even masters degrees in. It's called Marketing.
I would recommend getting into the marketing and advertising side of things, because SEO is the tip of the iceberg of what you can do with a brand or website.
If you have a great product or service then people will do marketing for you for FREE. However, I think that marketing strategy should be decided according to the need or business. SEO can be a powerful way to promote a website.
You nailed it...."Marketing" overall is where it's at. Anything you do to promote your product or service is marketing." Branding" your product or service is the bigger picture that a lot of "Internet Marketers" don't quite understand, especially if they are new. You cannot really brand a website that has no useful product or service. Therefore, all the SEO and Internet marketing strategies ultimately will fail for websites that have no real purpose or value.
I made some eral great experience with :
PressRelease Submission (Combined with a bit seo to rank your realease)
Document Submissions (I think it´s a bit outdated, but works still fine)
Social Media Marketing
I think social media network and video submission will be prefered. By joining social networks you will bring more and more traffic to your site, also can popular your brand