First of all, if you are interested in establishing yourself as an authority in your niche, then get a domain, even if you want to keep your blog on blogger, to remove the cost of hosting and escape from the trouble of having to keep updating scripts. The reason simply being that a domain is always more easily brandable and rememberable than a sub domain.
Having said that, having your own self hosted blog on possibly a VPS would allow you to try and implement/test things out, which would not only provide you with experience, but an avenue to showcase you skills.
Also simply “sprinkling” your links over at various places wouldn’t get you much traffic and might even get you branded you as a spammer (depending on how you go about posting links).
What you need to do is spend time at those forums, contribute positively and build a rapport and only post links to your blog when the situation and discussion demands (having one in your signature is alright if allowed by forum rules) eg. if I give you a link to my blog post regarding
how to effectively get traffic from forums, it would not only help the reader i.e. you, but also be on topic to the discussion taking place and wouldn’t be considered as spamming by most. However if I were to go ahead and do the same in say
How to change the Skype chatting style, it wouldn't be helpful to anyone and would actually be considered as spamming by most!
Apart from this, try and work on link building by submitting to free directories and other sources, also link to your post from Twitter and Facebook if you have a following there to ensure that new articles get hits. Guest blog posts on popular programing blogs would also help you get more exposure and traffic.
Also internal linking is quite important, so in case you are talking about something which you have explained in detail in an earlier post, then link to the older post to keep traffic flowing from new to old.