To rank in high positions of Google's results, can publishing contents to my website and social bookmarks to be done at the same time or with delay?

For me, it's better to publish your content in your website first and make it best before submitting it social bookmarking sites. If you would think of it, submitting pages to bookmarking sites without a good content would be useless for there are no interesting to read on.

You also have to do one thing is to link to related sites means those sites which are in your niche.

Social bookmarking is beneficial but do't build links on only social bookmarking try to build relevant back links for better results in Google.

You should publish first the content on your website before submitting it to social bookmarking sites so that the content you added will be crawled and read by search engines and will be added to their database.

Only Social Bookmarking may not work, you also have to use other methods of link building like blog commenting, forum posting etc.

When publication of new contents are done, spread it through blog comments. You will get quality backlinks and visitors as well.

Yes do go for link submission but always use quality and live links

I think form starting of your website, you should use directory submission and bookmarking, it would work well.

Social bookmarking is very helpful in increasing page rank, directory submission is also very helpful in this case, I do only directory submission and it helps a lot.