I see some of my friends do reading updates by posting a blog -- write the percentage and status as a blog post. However, I find that if you want to only update your reading progress by percentage -- without adding 'status text' -- you can also do that. I try to write the tutorial here, I hope that it is easy to comprehend ...
1) Login to your account. Go to your dashboard (booklikes.com/dashboard) or blog (booklikes.com/blog)
2) Choose the book whose progress you want to update. In my example, I want to update my reading progress of "Cursed". It shows 8% right now.
3) I click the cover so this screen appears
4) Click the Currently Reading button. You will get a screen like this.
5) See the number "8" there on the Progress (optional)? Just change to whatever percentage you want. I changed mine to "9"
6) Click Save. And you're done.
By the way, You cannot immediately see the change, just refresh your booklikes blog/dashboard to see the update. As you can see, "Cursed" reading progress shows 9% now.
Again, this is only if you want to update the percentage but don't want to add any text as status.