Download the correct iso. make sure you know 64bit or 32bit.
Make sure your system meets the requirements, especially if your going for ubuntu 14.04 this is not a light weight distro. since your using windows 8, i assume your system qualifies.
I strongly suggest a bootable usb flash drive with atleast 2gb avail.
Programs to create usb:
- unetbootin, it is simple and almost impossible to mess up
- universal usb installer.
Before flashing the iso. image you should make sure your usb drive is formatted, and i suggest formatting to fat32.
Some say to create a small partition for misc. data you might want to use for backup, but they leave out that if you are going to do that, the misc. data partition must be ntfs and it has to be the first partition.
Boot up and hit f12 (sometimes other keys depending on the computer) during startup, this will bring you to the boot menu, go over to boot options with the arrow keys and then hit enter to drop down the list of boot options, arrow down to your flash drive and hold shift and press the + sign to move it into the number one spot.
- reboot your computer now and it will boot into the live usb, and if everything was done correctly you will be running ubuntu 14.04 live session. now what is supposed to happen is, your supposed to be able to install ubuntu either as a complete install or side by side (dual boot).
DO NOT USE WUBI (installing from within Windows).
I suggest going with a regular install and when ubuntu asks if you want a side by side or full, you choose your preference. either way, you will have to partition your hard drive, a lot of people say that ubuntu handles that for you, but i strongly suggest you do this manually to make sure its done the best way possible. when partitioning the hard drive, i would create the desired amount of space for the ubuntu side, say you have a 1TB HDD, and you want to give half around 500GB to ubuntu, i suggest formatting the ubuntu side in EXT4, from there you will want to leave something called a linux-Swap partition off the back, usually double the amount of ram you have is a good size, so 8gb ram the linux-swap would be 16gb, it can be smaller and it wouldnt hurt, but i wouldnt go bigger. also, seperating the two partitions i would leave about 2mb of allocated space. some people like to divide their linux partition up more, a spot for the bios/boot another small spot for the system files but i think thats over kill and ive never had a problem with the way i do it.