You just have to make sure they're good quality, unique articles submitted to directories with decent page rank. And you should have lots of variety in your anchor text in your author bio-box links. Also, it's a good idea to just not use any anchor text at all occasionally.
Now a lot of website owners pay SEO companies or individual freelancers to build such links to their sites. But doing this carries inherent risks.
Firstly, they may be using spammy techniques such as article spinning, which could harm your site. Also, many of these companies offer deals in which you can buy, say, 20 articles all at once. Now if you purchased such a package there'd be a strong chance that such a number of links appearing suddenly would result in some kind of penalty from Google.
If you did suffer as a result of using such services, you'd have to get those links removed somehow. It's highly unlikely you'd be able to get the people who submitted them to remove them -- at least not for free. So you'd probably have to hand over money to a company that specialized in bad link removal. Either way, it would cost you.
However, if you were to do all of the article writing and submission yourself, there'd be a couple of advantages. Firstly, you could make sure that those articles were of a good quality and in directories that were well regarded by the search engines. And there'd be no way that you'd be able to overdo it, unless you devoted several hours a day, every day, to the task for a couple of weeks non-stop.
And in the rare event that this technique were to backfire on you and you needed to remove those links, you'd know exactly where they all were. So you could just go back to those directories, log in and remove them.
You'd be back to square one, of course, and would need to figure out how best to continue with your SEO efforts. But at least you wouldn't have had to fork out any money to neutralize the issue.