I recently went tubeless for the first time and found it really frustrating until I’d sorted a process that worked for me.
I did two sets of wheels – one TLR and one not, same with the tyres. If I’m honest it didn’t make a blind bit of difference to the end result.
I found the following……
Gorilla tape sealed the rims first time unlike the proper tape which was a disaster.
A track pump was hopeless, I splashed out on an Airshot and suddenly they were sealing first time. That doesn’t mean a ghetto inflator won’t work but I didn’t trust it to hold 140psi which is what I found I needed although I do like the conversion of a fire extinguisher into an air tank.
Remove the valve and use the Airshot to blast the tyre bead into place. Deflate and add the sealant, replace the valve then inflate tyre again.
They weren’t 100% airtight straight away but over the next 24 hours they sealed up.