Many Newbies are still confused about these options and whether they should choose the Power up 100% or 50%/50% Payout . In the bottom right corner of your post you can see a drop down box "Rewards ", where you can choose between three options:
Powerup 100%
Many users are the opinion that 100% Steem Power posts would be more popular and gain more upvotes. It shows you are dedicated to the long-term growth of Steemit and aren't going to withdraw your rewards quickly. So when you choose the "power up 100%" all your earnings from that post goes into you wallet as Steem Power. So actually your payout will automatically be converted in Steem Power and will not be liquid.
Default (50% / 50%)
That means your reward for that post will be paid to you in 50% Steem Power and 50% Steem Backed Dollars (SBD).
I have always had 50/50 payouts, because I needed some SBD to promote my posts and run the contest. You can choose this option if you wish to trade, cash out or powered up.
Decline Payout
With this option you won't earn any payout..
How to get Steem Power
Your Steem Power determines if you are a Minnow, a Dolphin or a Whale. So if you want to to get bigger upvotes, work on getting more Steem Power. Thats the only way to grant larger upvotes to yourself and others. There are many users running contests where you can win Steem Power. If you are lucky you can win it or It can be gifted to you. You can also buy Steem Power Delegation from 
And the easiest way is to earn it. Write good posts and be active on the platform. Be more engaging in your conversations and comments. As a newbie you can choose the Power Up 100% to get your reward as Steem Power.
Thank you for reading and hope is was helpful :)
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