How do I use 1/8” Router Bit On A 6mm Collet Makita?

I live in Europe and bought a Makita RT0702C Router for my MPCNC. It came with a 6mm collet. Everyone suggests using a 1/8” router bit. What should I do? I don’t wanna use adapters, I’ve read that it makes rigidity worse and breaks the bits.

i’m in australia, my local bit supplier (endmill.com.au) has 1/8” collets for the makita router available. no doubt there will be a local to you supplier that also carries them.