dual boot - How to make dualboot (2 linux distros) - Ask Ubuntu

can give me step-by-step guidance how can install on laptop(that has 1 hard drive) 2 linux distros(kali linux , lubuntu 16.04)? i'm stuck partitioning. how should separate drive? purpose give kali linux 50 gb of space , rest lubuntu. suppose see grub on boot, can select os launch.

in case not separately looking separate harddisk partition folders under linux distribution (for eg: separate partition /home /usr /etc). assuming aware how install linux , using gparted etc.

install first os suppose kali. in partition details window select manual. create 3 partitions 50 gb ext4 kali (here set mount pint '/' without quotes, keep aside 4 gb swap, format third partition whatever space left ext4. install , boot kali. verify kali works , have 3 partitions.

now next os, in similar fashion insert bootable usb or disc lubuntu, @ partition prompt choose manual. select third partition, , set mount point / (this root linux/unix). no need touch other partition. continue setting username, password or other settings if any. wait lubuntu install. once done reboot , should see entries kali , lubuntu in grub menu.

if reason kali or lubuntu's entry not available in grub , directly loads os. here can do:

1) if lubuntu directly boots: open terminal , write following command:

$ sudo update-grub

2) if kali directly boots: since kali linux based on debian, same command lubuntu should work fine.

that should generate grub , on next reboot should able see grub entries both oses.