When it comes to choosing the right Adsense color and size you need to understand one thing
, all websites are different. If you look all over the internet there are lots of different Adsense colors and ad sizes and the reason for this is because all website traffic is different and people who are on dog training websites might like different formats than those who are searching for diet pills. The best way to see what your visitors like the best is to test out the different colors and sizes.
For most people testing is something they don't like to do because they want to see the best results right away and testing takes time. Just because testing takes time doesn't mean you can't still make money. The best banner size to use is the large rectangle in Adsense default and place it in the middle of the page right above the fold. Doing this will make every person that visits your website see the adds and if there is anything they want to see then they will most likely click on it. Just make sure you still text your Adsense placement because you can be making a lot more money if this isn't the best spot.
I have been using adsense on all of my websites for years and have gotten really good at the placement and formatting, but it has all come to me with lots of testing with each new website I make. The best thing to do is just start now, I fought for a long time to try to make Adsense work without testing my position and color and it didn't work, I eventually had to test each site. Just know that you aren't alone and everybody who is making over $1,000 a month from adsense has done this exact process. If you want more ideas to make money other than adsense there are many great options out there for you.