Things you should do before installing new rom in android

Installation of new rom is fun.
But sometimes this fun becames headache if you don't have not proper plan.
Sometimes you find some corrupt roms and after installing them cause boot loop
So do few things before installing any new rom
1- Firstly create a backup of your IMEI.
How to create???
Download and install mobile uncle tool open it you will find option easily
2-Create full backup of your original/present rom
How to create???
Open recovery which you are using, like if you are using twrp then boot into recovery and you will easily find backup option...
create a full backup.
now switch on your phone and check where these two backup are (IMEI, Rom )
means if they are in internal/phone memory then cut and paste all in memory card.
why this backup is important???
If your new custom rom cause any problem then you can easily restore old rom.
And why this IMEI.bak file is important???
Because after installing new rom sometimes your IMEI corrupt and because of corrupt IMEI your sim will not work..
And one more thing if you know use of titanium backup app then use it for backup of your app like what's app YouTube, Allo etc etc...this app is awesome

So guys do these few things before installing any new rom then it is good for you
Thanks.