LGB new to this DCC help?

[dunnyrail]

12Pcs T Tap Wire Connectors, 2 Pin Low Voltage Quick Splice Solderless with no Wire-Stripping Electrical Wire Connectors for Wires Connection 20-22 AWG, Heat Resistant for 12V, 24V DC Automotive
12Pcs T Tap Wire Connectors, 2 Pin Low Voltage Quick Splice Solderless with no Wire-Stripping Electrical Wire Connectors for Wires Connection 20-22 AWG, Heat Resistant for 12V, 24V DC Automotive : Amazon.co.uk: DIY & Tools

Look at the image for black to black, then yellow to red will be the other side.
If you're using them to just connect 2 to 2, then only come out of one side ? If that makes sense.

Those do look like a good solution to me. You should be able to run a few feeds out of each of these depending on the wire size.

As for the Gartenbahn clamps, have a look at prices cos if a normal clamp is less than the price of 2 of the power clamps, you can always cut the normal ones in half.