Question on Stacking Gems Across Gear

Hiya - if I stock my bow's sockets with modifiers, say +crit strikes +accuracy + crit damage and +cold damage, do those modifiers apply to all attacks with that bow? Say I'm using 5L armor for offense, do the bow modifiers stack with the gems in the armor?

You would do well to read up on the very basics at least, check the stickied beginner's guide.

But it works like this, in a nutshell:
It doesn't matter where the slots are, the only thing it matters is what's in them.
Support gems only apply to the active skill gem they're linked to within the same item, the order doesn't matter.
A support gem linked to multiple active skills will affect all of them.
An active gem linked to multiple support gem will be affected by all of them.

I'd already read the beginners guide; it didn't answer my question. Thanks for the reply.

It'd be interesting if you could link gems across items. For example, anything you hold in your hand gets linked to the gems in your glove. Any attack gets linked to the gems in your weapon, etc. That'd produce some awesome combos.

In fairness to the OP, that beginners guide is not very beginner. It leaves out a lot of basics. When I started I was midway through act 2 before I knew that right clicking the mouse did anything. I assumed that when you put the gem in a weapon that it was automatically used when you used the weapon (left clicked). So if I put burning arrow and split arrow in my bow, I thought it automatically used both every time I used the bow. There was no graphic of split arrows, but how would I know what the graphics were supposed to look like? It's completely intuitive to assume that placing a bow gem in a bow "upgrades" the bow.

There was nothing in the guides that said anything about this.

To answer the OP:

It doesn't matter where the skill gems are located. You can put a bow gem in your shoes or gloves or anywhere else. Once the skill gem is placed on any gear it becomes available for use. To use it, click one of the icons at the bottom of the screen. By default they represent the hot keys QWERT and the three mouse buttons. For example click 'Q' to bring up a list of all available skills. Click one of the skills to assign it to the Q key. You can do the same for the other keys and mouse buttons.

The above is for skill gems. For support gems (they all say "support" in the key words), it must be linked to the skill gem. That means it must be placed on the same gear as the main skill, plus it has to have a line linking the sockets.

So if you have Burning Arrow, and place it in a green socket on your gloves. Then later you get Accuracy. You must link the Accuracy gem to your Burning Arrow gem. Accuracy also needs a green socket, so your gloves would need a second green socket linked to the green socket where you have Burning Arrow.

Once you link your support gem to Burning Arrow, every time you use Burning Arrow, it automatically uses the support gem Additional Accuracy. The location or gear where they are placed doesn't matter. They just have to be linked to each other on the same piece of gear. In other words, if Burning Arrow is on your gloves, Accuracy also needs to be on your gloves, and linked. If Burning Arrow is on your bow, then Accuracy also needs to be on your bow, and linked.

Support gems do nothing at all to the weapon itself. They only affect other skill gems that they are linked to. So it has no affect if you use the default left click to use your bow. (Although you can assign the left click to use burning arrow if you want)