Missing social media icons from header

Hello,

Like an idiot, I suspect I have changed something but cannot recall what i changed !

I am convinced that on starting to build my site – http://www.louisawade.co.uk – that twitter, facebook, youtube etc icons appeared in the header and footer.

I turned them off as I had no need for them at that time – i wanted a clean screen to help me concentrate when working away on the content.

Now though, I would like the icons back but I can’t work out how to bring them back.

I tried via appearance – customize – header social options – then inserted the facebook & twitter URL’s but the icon & link is not then restored.

I cannot see anywhere else short of opening the bonnet and fiddling with php to bring them back.

Can anyone give me a hint as to what I am doing wrong ?

Many thanks.