Social Bookmarking - one account or multiple?

Hi all, Unfortunately, I do not have the funds to do this automated yet so I am doing this manually.

I am getting started creating all my accounts for social bookmarking, but there is one thing that I need a recommendation on.

Should I create multiple accounts, one for each niche, and only bookmark niche related to each account?

Or is it better to create fewer accounts and bookmark multiple niches so that it looks less spammy?

My first inclination, is to create one account per social bookmark site, then bookmark several different pages across different niches so that it appears more normal, plus it is a hellofa lot less work.

Suggestions? (other than to purchase something I can't afford right now)

I don't know how clever Google is, but I always wonder that bookmarking all your pages under one account will look more or less suspicious. There is a chance Google would consider it as self promotion if the bookmark account doesn't have other random bookmarks in it.

This is probably the reason why bookmark software focuses on creating lots of different accounts to diversify who is making all the bookmarks.