Some advices are obvious like trying to not degrade your RNA during extraction. But others are trickier, like the need immediate impeding of natural mRNA degradation (some mRNA has a very short half-life).
When I was working on mRNA, we stop very quickly the bacterial metabolism by using cold ethanol at-80°C. You can check the protocol on the following paper.
Article Transcription attenuation associated with bacterial repetiti...
I think the gold standard for RNA extraction from bacteria involves using the hot phenol method. For a metabolism stop solution, add ice old 10% Phenol in Ethanol.
Thank you very much for the help, I'll try to do it and since is my first time with RNA extractions I wanted to know some experiences and this really helpfull, specially because I've heard of how easy the mRNA gets degraded.
I would say stop the reaction either with dry ice or if you have access to -80C then prepare a mixture of acetone - methanol which will stop the reaction and you can recover the mRNA. Finally if you have boiling liquid nitrogen, then its all very easy.