Well, this is just a sharing from me. I am definitely not the expect here. I may be wrong, so do comment and correct me.
Before I upvote any post, I will first go to check the balance of my Voting Power at https://steemnow.com
As you can see, my Voting Power now is 75.55%, which will be full in the next 29 hours.
Under normal circumstances, I will vote until the Voting Power is 72-76%. This is because every 2 hour my Voting Power will recover by 2%. So after 24 hours, it will be 24% recover, nearing or reaching to 100% again. For Friday i will vote until my Voting Power become as low as 40% because I knew that I wont be touching Steemit for the next two days, hence I have lots of room for my Voting Power to recover.
For every 2%, you can upvote 1 post. Then I will calculate how many post I can upvote on that day.
After that, I will go and choose my post using Steem Bot Tracker at https://steembottracker.com
There are a lot of Bot for you to choose from in Steem Bot Tracker. Some writer will be using a Bid-Based Voting Bot for the bot to upvote their post based on the bid they put into the Bot like an investment.
Then I will look for Bot that require a minimum of 3 SBD. Once I have identify the Bot, I will click onto the Details. This is what you can see:
You can see that 
I will then click into his post and do some evaluation:
This post is 4 hours old. I will consider to upvote this post because it had past the 30 minutes, hence 100% of curation reward will goes to the curator.
Then I will check on the Post Value & number of upvoter before I decide to upvote:
This post have 84 votes & $340.90. In this case I will not upvote anymore because there are some whale already upvote this post. What I am looking for is a post that is low in value at the time of upvote before any whale. So the best is below $5 for what I think
For example if the value is $5 now. You know that after some time, when the Bot upvote this post the value will go up by another $40.
Let me give you another example where me and 
Our Steem Power is so low that it may have no significant effect on a upvote value. After voting, I check our potential Curation Reward using https://steemstats.com
With me having a higher Steem Power, but my weightage in the upvote is much lower than
The reason can be found here in https://steembottracker.com/curation_calculator.html
So this is a little idea for you when you upvote someone else's post. Have fun earning with Steemit.
