So your voting power grows as you earn more Steem Power. When you and others vote on your posts you earn Steem, Steem Power and SBD.

When the price of Steem is high you'll only earn SBD and Steem Power. But right now it's low so you'll earn Steem, SBD and Steem Power.

How much you give when you vote is based on your Steem Power. Right now you have 0.955 Steem Power and Steemit Inc have delegated 14.046 Steem power to you as part of your account creation.

The actual dollar value of your vote (what you see when you vote on a post or comment) will fluctuate as the price of Steem fluctuates. Which is why it changes all the time. A couple of days ago my maximum vote was around 20 cents. Today it's probably only 15 cents. A month or two ago, it was 30 cents.

You get more SP by creating content and receiving votes on your content and voting on your own and others content. When you vote on someone else's work you get what is called curation rewards which is a percentage of the posts value.

The other thing I recommend you do is look for writing contests to enter. This is an excellent way to get quick recognition for your skills as a writer and to win some Steem and SBD as a prize. Look under the contest or writing tags for any contests that are worth entering.

Hope this helps.