Upgrading gems?

how do i upgrade my heavy strike gem? It says ready to level up or upgrade.

I'm new to the game, but have found this interface difficult as well. From what I can tell, there's an icon on the right of the screen you can click on. I can't find any other way of leveling gems.

If the + to level the gem is grayed out, then you must level yourself before you can level the gem.

When the gem is ready to level, there will be a little icon on the top right under your mini map you can click on. It has a little plus sign, click that and it will level the gem. If the plus is greyed out, you dont have the stats or level to bring the gem up to that level yet. Another way to improve gems is to use a GCP on them to raise their quality.

Left Click the + sign on the right side of your screen, or go into your inventory and Left Clikc the + sign at the bottom of your inventory.

on the right hand side of the screen, right before a gem is ready to level up, it will appear greyed out.. to inform you that a gem is almost ready..

if the gem is ready to level up, AND you meet the requirements for the gems next level, it will have a green + sign next to it.

if you right click this, you can dismiss it, and now you need to press I, then look under your inventory, a list of gems that can be leveled appears there.

if the gem is ready to level up, AND you do not meet the requirements for the next level, it will stay greyed out, and you will have to meet the requirements before you can level it.