How do you enable the "What-You-See-Is-What-You-Get" ? (blocy coding thingy)

Someone please for the love of my sanity help me enable this. Ive been looking all over the internet for 2 days straight. My sadness has increased drastically due to this. I'm writing 'formally' because if I don't, i will end up screaming like the child that I am. 

Please. Help me. :(