connector - How can I make connection on pcb (circuit board) holes without solder (for prototyping)?

I have a Pro Micro board (very small -- see pic below) and it has connector holes in the printed circuit board.

Best Non-Solder Connection (Easy and Removable)

I'm wondering the best way to make non-solder connections for doing my prototype work. By best, I mean easily removable while maintaining solid electrical connection.

Are there pre-made connectors for this type of connection?

What Part Is Most Conductive / Best Electrical Connection?

Also, how can I know I have a good connection? Is it the inside of the hole that has the conductive metal, outside of hole?

Front / Back Separate Traces?

And, are the front and back of the holes electrically connected normally or do they have separate traces normally?

One Idea: Would It work Very Well?

What if I had header pins pushed into a breadboard and then up through those holes? Then I connect my wire to the top of the header pin? Would it be a solid enough connection? Or would it not make enough electrical connection?

ie - would header pins make connection inside of holes and would that be enough electrical connection?

Edit -- I Wish They Made Banana Plugs That Fit This Wouldn't it be cool if you could use a banana plug type of connector. Then just plug in each one and put wire in hole and clamp it down?

UPDATE 11-11-2017 Interesting that in the time since I've posted this someone came up with a solution similar to what I was thinking with banana plugs: Hammer Header Male - Solderless Raspberry Pi Connector It's really for use on a RPi Zero but it's the type of snap-on header I was interested in at the time.

However, the installation is not easy so it may not be practical. Take a look at what you have to do to install it : https://learn.pimoroni.com/tutorial/sandyj/fitting-hammer-headers Probably easier to just solder on the header pins.

Answer

Use grabber test clips, which are basically like smaller alligator type clips.

Though regular alligator/crocodile clips may work, depending on the size or how many side by side ones you need. I have some really mini ones.

Yes, the pads should be plated on the inside as well as the top and bottom, electrically connecting them.

No, just pushing a standard 0.1" header into the hole won't work. They are not offset holes, or push fit tight. They are generously loose. Some people have used rubber bands but that's not very secure.