Who You Are
This is where you introduce yourself. Show off your personality and let people see a little of who you are as a person. Give yourself a face here, don't just being some faceless voice on the internet. Let people know who you are and that you are passionate about the subjects you are addressing, and writing in general. This section can stay the same across your multiple signature versions. This maintains a consistency of branding across your signatures and posts.
Establish yourself as an authority in the subjects you post about by providing your relevant credentials in your signature. Telling people that you love writing might be great when writing a post on grammar, but on a post about engine maintenance that isn't a very big selling point on why readers should listen to you.
Drive Readers To Your Other Content
This is where you can give links to your other content that is related to whatever you have just posted about on InfoBarrel. In this way, for example, you can link to your blog on cat grooming if you've written about cats, or anything pet related. This allows you to send some traffic to your other content, while hopefully sending readers to information they will find useful.
More InfoBarrel and Affiliate Linking
You can end by linking to your own InfoBarrel page, and/or you can use your affiliate link to get someone to join and send little more money coming your way from the referral.
Using multiple signatures this way allows you to have more perceived authority in a subject. If you only have one signature that rambles on about everything you know, you can either come across as being conceited, or annoying since your signature may not relate to the article you have posted.
Taking the more simplified approach of just saying "I know a lot," isn't going to get you anywhere with readers either. This is a meaningless generalization that doesn't tell readers anything.
Don't underestimate your signatures, they are a powerful tool for getting more out of InfoBarrel, and your online money-making strategies.