I pull whatever car on with the electric winch in the front of the trailer.
I have a 6 foot 1" strap with clevis ends, these go around each lower trailing arm in front. The winch hook attaches in the middle creating a bridle.
I use heavy chains in the back with snap hooks. I have nylon straps with nylon sleeves in 21" and 31" lengths(Tractor supply $20 ea, 10K pound rating). I wrap the nylon straps around the frame of the Spyder, the axles on the Formula Vee. Winch it in, hook chains, tighten winch.
Nylon straps:
https://www.tractorsupply.com/...-000-lb?cm_vc=-10005
Then I move to the front, and there I have ratchet straps with a hook, a nylon sleeve, and an adjustable loop to secure. Ratchet them down. NEVER depend on your winch to keep the car in place.
These straps are called "axle straps":
https://www.macscustomtiedowns...KEAQYASABEgLAa_D_BwE (just for illustration)
Always drive a few to ten miles and recheck tightness. Sometimes the car moves and settles, sometimes it doesn't move. It really depends on how straight you get it.
My Cayman is a different story. The trailer has ZERO room to open the driver door. The front towhook is offset to the right of the car, so I winch the car on backwards. The tow hook screws in behind the license plate(2 little screws).
That car gets straps through all 4 wheels, it is so low it is impossible to get under.
I reach in the open window and set the emergency brake once the car is tightened down, and I recommend leaving the car in neutral(not good for the transmission to rock back and forth if the straps get loose).
It is common sense and common practice to have EACH single strap rated to MORE than the weight of your car.
A friend had a 24' trailer with two racecars in it and had a MAJOR accident last summer. Totaled the truck and ripped the ball hitch part of the trailer both in half and completely off the trailer. My friends were OK, walked away. The trailer contents were completely OK because the cars were well secured with GOOD tie-downs.
They got another truck, repaired the trailer and continued to the races that evening.
EDIT: If your trailer has E-track in the floor, wheel nets are a GREAT option. I don't have that, just the factory 4 tie-down points.