At first, change your Steem Dollars to Steem. You can do so at local Steemit market: https://steemit.com/market
Powering down - transfering Steem Power to Steem - takes 13 weeks while each week a certain percentage of you Steem Power is converted. I believe it is not wise at all but it's your choice.
Do you use Steemit chat? https://steemit.chat Meet me there at channel "general" for more hints. It would be much swifter than comments.