Which way you start is your preference, but I do not recommend changing directions as you go along. I usually work from positive to negative because this convention is more traditional, but it is just as easy to work from negative to positive.

The important things to remember when wiring an electronic circuit are:

1. Be sure that the power is disconnected while you are making connections.

2. Use the right tools for the job.

3. Work methodically to avoid making careless mistakes such as crossing wires, reading the schematic incorrectly, or failing to make a connection.

4. Work carefully to avoid making poor connections that could cause your circuit not to work properly and possibly even damage your electronics.

5. Check over your work carefully until you are fairly sure that you have made no obvious mistakes before you turn the power on. (A good fast check is measured circuit impedence with an ohm meter compared to calculated values on your schematic.)