I learned how to do this during lab hours with Wesley this morning. Thanks for asking how to do it because it helped me reinforce what I learned today.
When you login to your blog spot page there are links across the top of your page. Click on the customize link. You should get a page that says add and arrange page. On this page there is a link that says add a gadget. Click on the add a link gadget. On the left side of this page there are links on the left side. Find the link "featured "and click on it. Scroll through the choices until you find the one for twitter that has the blue bird on it. I believe it is the tenth icon and choice. Click on the plus sign and you should be taken back to the Add and Arrange page. This time you should see the twitter link where you had originally click on add a gadget. I then clicked on the twitter link and dragged it to a spot on the right side of my page. When you have done all of this the last step is to click save.