There has been over hundreds of threads here in this section just asking “Yoyo1 or Yoyo2?” You need to say your preferences. We can’t help you choose. Just like a OneDrop 54 is best for them and then a month later they post and say they like under-sized. Here are most things you need to say:
Size
Your size preference is needed because (as said above) many yoyo’s have different sizes. Although this is not too important, still needed to help choose.
Weight
There are many different weights on each yoyo. I know that most yoyo’s can range from 63-73 or even more or less, but there are feel differences too. Having the right weight can sometimes change your throw, play etc. And again, not the most important, but it’ll be best if you say.
Feel
Now, you want to say this because this is the shape of the yoyo. I heard that the Protostar’s H-Shape is very comfortable but when I got it, my fingers had a hard time fitting in with the yoyo. I can throw hard, but when you don’t like the feel and shape, it’s hard to go with it.
Your Goals for your yoyo
Each specific yoyo has their own advantage and dis-advantage. No yoyo is perfect. You may want to mention that you just want one to chanllenge your skill and the POPstar or Mighty Flea will fit you well. If you want to try stacks, well obviously, stacked yoyo’s would be cool.
Grindability
Mentioning if you like to grind or not is another factor. Some yoyo’s grind better than others. Some yoyo’s even can’t grind at all. Though you don’t choose a yoyo because of this but this is still important.
Skill
Your skill level is very important because a begginer would not be recommended to choose a 888x to start off with. You can say your skill by according to Andre Boulay’s videos or in the learn section of this website. Rarely, does anyone judge their skill by the tricks they know.
Style
This is somewhat needed. Although it is very very obvious you can tell from a looping yoyo to a string tricks type of yoyo. This is for Offstring too, they look much different. But 1A, 3A and 5A are very similar. Most people already do this but I am just going to mention it for safe.
Floatness
Some people may find this useless but actually, you choose a yoyo by this. By floaty, I mean how fast it speeds across tricks and how it feels. A capped Legacy, to me, seems heavy and not seeming to move.
Appearance
This is useless for some reasons. Every yoyo in the market now look good and if you can possibly find a yoyo that seems revolting or “looking-bad” to you, I doubt you’d even find one. (Doesn’t make sense) 
Price
This is very important. Every thread on what yoyo to choose MUST have this preference. As you already know, yoyo’s range from a few dollars to 460 bucks. It’s just important and if you don’t have this one, it’s hard to choose. BUT THIS IS EXCEPTIONAL IF YOU HAVE NO LIMIT
Brand
You don’t need to name this one unless you are a fanboy or fangirl. Really doesn’t matter.
Any critism won’t be tooken offensive. But try not to be a hater.
I hope this helped!! ;)