I am not going to overload you with a lot of information here, I will start with some basics.
You don't need software or laptops, just a pen, paper and clipboard, a good tyre pressure gauge and pyrometer (infrared temperature gauge). Decent quality units are available online for less than $50 each, so they are an affordable and essential tools.
The critical aspect of reading tyre temperatures is that they must be done immediately at the completion of some race pace laps done at the very moment the car pulls up in the pits. Your pit crew (If you have them) must be waiting ready to converge on the car armed with the pyrometer and clipboard the moment you pull up.
It's best to always start with the working tyre. The working tyre is the tyre that is taking the majority of the load and is usually the outside tyres and mostly outside front. At Wakefield Park, the working tyre will be the front passenger side (L/H) as this is a clockwise track. At Sydney Motorsport Park, the working tyre will be the front driver side (R/H) as this is an anti-clockwise track.
Measuring tyre temperatures involves taking readings at three points across the tread face.
These are the outer edge, middle and inner edge. Inner and outer temperatures should be taken at a point approximately 25-30mm from the sidewall. Pyrometers usually feature a laser pointer to guide the position of measurement and it is best to point into the valleys of the tread pattern in order to avoid inaccurate readings from dust & debris on the tyre surface. Be consistent with this measurement point with each and every measurement session.
- Middle higher than inner and outside edge. Tyres are over-inflated.
- Inner & outer higher than middle. Tyres are under-inflated.
- Inner edge hot with middle and outer edges progressively cooler. High negative camber. However, inner edges slightly higher overall is considered OK
- Outer edge hot with middle and inner edge progressively cooler. Not enough negative camber. In this situation, you are throwing away cornering force and traction. Work on optimising your camber but if your'e competing in standard class, your only option is to increase tyre pressures slightly to achieve a more gradual temperature spread.
At the end of the day it will be "traction, traction, traction" that will win the day, and this is all about maximising the contact area of those four tyres.