which keyword(s) should I aim for ?

Maria, I suggest you to use Google Keyword Tool. It has many options available. Look for keywords that are medium or low in competition. if not available, then you can make longtail keywords to add more visibility in SERPs.

 

Any ideas on what keywords I should try to optimize for? My site is a webmaster blog site that gives some info on how to manage sites, generate , freebies, etc. It also shares my personal experience as an amateur web designer/entrepreneur.

I don't want keywords that are very competitive. I am thinking about trying for some keywords that are good, but not as competitive as like "webmaster resources"

 

you can get a bundle of them by the right research

 

just do some analysis and combine the characteristics of your business line, you always can find some niche keywords, they are not competitive but very effective for your business and it is easy to rank them well. Currently, i am using Google Analysis and Adwords, you always can find useful information from them. Such the percentage of the old viewers and new viewers, how many come from Ads and how many come from organice search. Still, there are tools for webmasters, i am learning to use these tools. So, you may try these tools and see what you can do.