High bounce rate is bad for your blog. Bounce rate happens when people start leaving your website without going to next page in specific amount of time.
First try to understand if people who are leaving your website are coming from where? Understand root cause of problem
Your bounce rate on pages and bounce rate on website are different things.
You may have to spare some time to first identify reasons for bounce and who are bouncing off your website.
Just trying to implement tips and tricks found on blog will not help and you may increase bounce rate also
There is nothing like 60% or 70% bounce rate is good.
If you can reduce your bounce rate, you will be able to increase your page views and more page views means more money if you are using AdSense of similar monetization.
For this you will have to start with your Analytics and start recording data to see how was your bounce rate month by month and when it started to increase.
Segment your traffic – Organic, Referal, Social and direct and see which traffic has high bounce rate.
Try to understand from there it may give you some idea
Also see pages with high bounce rate and then analyse them.
Is it due to slow loading pages or videos or some images etc
Is high bounce from mobile or from desktop?
Also see if this is due to content?
Was that bounce rate increase after you changed theme?
Digging deeper will help you optimize your blog for exit rate, bounce rate, it may also increase your page views etc.