Append HTML Signature in Gmail
By default Gmail doesnt allow HTML signature in outgoing emails. Means all tags you put into signature will appear as it is.
So there are multiple ways to overcome this problem. Simplest is too have a HTML editor and copying HTML signature into Gmail. This method is good when you have to do 1 or 2 mails everyday.
And the other method is by using Greasemonkey, but greasemonkey is for Firefox only.
The trick is nothing too extravagant but you will need to have Greasemonkey installed to get the job done. Here is what you have to do.
Download Firefox browser if you dont have it.
then, Install the Greasemonkey script into your firefox browser.
After that you’ll need to have the HTML code for the signature that you want to insert. Once you have that just go to the Greasemonkey script manager and edit the script’s HTML signature.
Once done, every time you compose a NEW EMAIL as well as reply to any, your signature will be appearing automatically 
If you are using plain-text signature in Gmail, that will be also added to new mails. You can either use both or remove old signature by going to Settings > General > Signature.
