Help with installing the rt5370 150M USB WiFi Dongle with Antenna

Hello there,

I recently bought from Ebay the following [WiFi Adapter][1]

[1]: thought i would only need to plug it in and activate the Wireless Adapter, but I don’t seem to get any wifi signal (while I can connect using my smartphone standing near the RPI).
i googled the problem and found many solution regarding typing in different commands and what no.
my knowledge of RPI and Linux is very limited so i don’t even know where and how i should type those commands.
can someone please give me the dumb version of how to get my wifi adapter up and running with the OSMC installed on my RPIB+?

thanks in advanced.