Correct and appropriate use of post title will help you to attract more visitors to read your content. So make sure that your post title should contain your targeted keywords with unique and descriptive content. Try to make your post title exciting so people will attract to read it.
But which blog are you use, Blogspot or WordPress?? If you using WordPress for your blog then you can install plug-in like "All in SEO Pack" it will help you to create Metas for each post for SEO point of views.
1. don't write more than 60 characters
2. Use main keyword but don't use variation of same keyword twice in title, add only once because Googlebot looks for keyword density in title
3. If your website is in wordpress then use "SEO Yoast" plugin, it will guide you more
Keep all of your page titles different and unique. Why? The example I like to use is this. Imagine having a great author who has written many books, but all of them have the same titles…would you read all the books to ensure they are indeed different or just assume they’re all the same? Now apply that to search engines.