If you are running a blog on blogspot and wanted to Setup Blogger Custom Domain and change address myblog.blogspot.com to myblog.com then here is step by step guide. I just recently changed that when I was doing this faces some difficulties like where to fill the entries how much time it take or are there are current or not because I don’t want to waste my time to figure how this work.
Please note this whole process can take time about 24 to 48 hr some time result can be comes 1 hr so it’s depends on ISP for update.Also read How to Import WordPress to Blogger Posts
Here is Guide to Setup Blogger Custom Domain on Godaddy
Step 1. After login to blogger select blog and choose settings to edit settings like below picture.
Step 2. Open Basic settings into publishing section click on + setup 3rd party URL for your blogs like below picture show instruction.
Step 3. In the box add your website and click save that will display 2 code that you need to enter on domain provider website where your domain is hosted may Godaddy.com or any other I use Godaddy to verify my ownership.
Mapping domain over hosting side go to Godaddy.com and login their
Step 4. After login to godaddy website you will see dashboard like this then click in domain it will show the list of domain now you just have to click on Manage DNS button like below picture.
Step 5. Then a page open like below and click on add record to make new A and CNAME record on godaddy website you can also delete any old record present on A record section.
Step 6. Now choose CNAME (Alias) from record type list and enter details provided by Blogger. www should be enter into Host and ghs.gogle.com into Point To. You need to create two records for CNAME one this another is that Blogger provide your as same so we can continue setup blogger custom domain.
Blogger Custom Domain Redirect www and without www
Step 7. Now you need to make A record as well and point them to Google IPs because without your blog open only with www to open it without www you must add A record on domain hosting.
Here are IP for A record
216.239.32.21
216.239.34.21
216.239.36.21
216.239.38.21
Enter @ into host name and above IP in Point To section make 4 records it’s important into setup blogger custom domain like below picture then don’t forget to save it.

Now you just need to wait and watch your domain should be point to blogger within 24hr other it should be update within few hour.