How to add Blog Button and code

Hi, can you please direct me to instructions or help me with how to add a blog button and code to my side bar. I have created by blog button, now just don’t know how to add it to my sidebar.

I did follow a set of instructions I found, but somehow this deleted every other widget I installed eg facebook, adsence, twitter, christmas countdown. And since my adsence $$ has decreased dramatically, don’t know what went wrong. I don’t want this to happen again.

Appreciate your help!