After you create your Google form, you ned to click the Send Form button on the top, right of the page. Next you will see the link to share, Send form via email or Embed. Choose Embed.
Now you will have the Embed form dialogue box come up. You can copy the HTML code in the box. First notice the size of the form in pixels.
At this point it is a good idea to change the form size to fit your blog. Typically you want your width to be around 500 pixels. The height is something that you have to play with to get right. I prefer to have the whole page of the form showing on the post. This means you will need to change the height of the embedded form to your liking.
I changed the form height to 400 because the form only has one question. Next you will need to click the HTML button on you blog post page. You will find it on the top, left side of the page.
Notice that I have already placed text and pictures on the post so you will immediately see all the html code on the page. I simply scrolled down to the bottom of the page and pasted the code I copied earlier.
The '<iframe src=...' is the actual code for the form.
This is what the page looks like now with the html for the form added. If you don't have anything already put on the post you will not see nearly this much code.
Now you click back on the Compose button and you can see the form is now part of the post. At this point you may want to go back and adjust the width or height of the form html to make it fit right.
When you are finished, publish your post and it will show up with the form embedded on it. Now all you need is people to come and respond to your form!