Is it possible to set the geo up on my car at home, what do I need?

yes.

Thin string, I used fishing line
4 axle stands, and a steel rule.
Glossy mags (Not those type) to make the car level and allow the wheels to swivel/move with little friction

And lots of time

For the camber/caster you will need a spirit level and an angle finder. Or if you want to spend money buy a bubble gauge

Look up String alignment

Cut an old number plate into two, put the two parts together with some grease between them - makes a great rotating platform for when you do it!

Very good results using string. I spent out a £1 and bought some bright pink(!) jewellery cord stuff, thin, flexible strong etc.

For camber and castor I printed off an image from this page https://www.merlinmotorsport.co.uk/p/ada-castor-camber-gauge-adaccg and stuck it on some hardboard, bit of above cord and a small weight, job done.

Took an afternoon (leisurely, lots of double-checking etc). And I started by setting the fronts parallel using some flat boards approx 24" long and 6" wide and a tape measure. Then did rears the same. Then started with the string. Car handles really well....perfectly even tyre wear etc etc.

So, what settings do I need to use? I have some written down somewhere from when the car was built by Toyshop but any useful settings for a trackday and occasional road use. Striker with IRS BEC