This sigil is used to hide objects in plain sight. No it doesn't make it invisible, it's more like distorting perception. It doesn't work the same on everyone and if someone that knows the object was there looks at it, they will still notice it there but it's also likely that they will completely overlook it. How the sigil works is difficult to explain, it's better understood when applied practically.
To use it you need only place the object on the sigil, stick the sigil to the object or place the sigil inside of it