First off,
1. What the keywords search vol? --> no point ranking total keywords vol less than 1k/mth even if you rank No.1
2. Are your site articles unique? --> already discussed trillion times and is proven, period.
3. Like above said, directory and bookmarking alone will not do any good. ---> Diversify the links from many sources
a) High PR Web2.0
b) High PR Doc Sharing sites
c) High PR Press release
d) Rss Feed submission
e) Video submission
f) High PR Article Directories
High quality is the key for the above mentioned linking sources. 5 - 10 submits on each of them will be just fine. Remember using these as tier 1 with unique articles.
4) Tier 2 can be dripped feeding daily but with caution with wiki, bookmarking, forum/social profile.
No secret in SEOing, just research on the keywords difficulty level and volume, and 80% of your job is done. Remember the 80/20 effect.
Cheers and best of luck!