FIRSTLY, you need to buy TENX PAY visa card by simply downloading their app which is available on android , web application , IOS.
please take note : i am recommending this company because their vision is very transparent and profitable for users . for more detail ,please go to their website : - https://www.tenx.tech/
after you bought then you can easily spend your steem & steem dollar but just need to change your steem & steem dollar in bitcoin because this company currently working through bitcoin payment but in future they have many plans like adding litecoin , dash ,may be also steem sooner or later and so on.
okay , let me show you how you can do this?
Go to tenx app which you installed in your device then go to bitcoin deposit address and copy it .
after that Go to https://blocktrades.us/
Then Select: Steem to Bitcoin(shown in the picture) - Insert you Bitcoin Address(address where you want to send bitcoin) - and after your address shown valid then click "Get Deposit Address"
Then follow below picture where blocktrades will give you "MEMO" address and request you to send steem or steem dollar whichever to "blocktrades" with memo.
Thats it, its very simple, fast and secured but just take note "do it carefully".
"if you are still not sure then you can send small amount at first so that you will get enough confident in just low risk "
also kindly take note " Tenx Card currently working in European countries but soon in 2018 or before will be launching in USA and Asian Countries."