Give relevant name to the image:
First, you need to realize that image which you are downloading needed to be given a particular name. By particular name I mean the name which has some relation with your post. For example, if you are writing your first blog post to blogger the image you upload to this article must be named like Blog First Post.png so that it relates to the content.
Search engines can read images they depend on tags and title given to images. Therefore, to tell search robots about the image we should add title and alt attribute to image. In blogger once image is added to post click on image and select properties. A pop box will open you can put image title in the title text box which should be relevant to your content and in alt text box give a small 4 to 5 word description of the image.
These simple tips can drive a lot of organic traffic to your blog so you must take care of this simple tips. Now It's your turn to share this post with your friends and write your precious views in comment box till then Peace, Blessings and Happy Optimizing.