Buy VMWare Fusion, download, and install (write the serial number during installation). To get quickly started, you download a trial version for free and later buy it and register the serial number (easy).
Go to http://www.ubuntu.com/desktop/get-ubuntu/download and choose the latest 64-bit version. Save the downloaded Ubuntu file at some place you can recognize later.
Launch VMWare Fusion. You may get a window like this:
If you do not see this window, try to find a New button and click on it.
In newer versions of VMWare, double click on Disc or disc image instead.
The user now will be asked to download VMWare Tools for Linux. Press download (and remember to be connected to the Internet while doing this). Note that this question is asked only the first time you install a Linux VMWare virtual machine.
Now the default configuration of Ubuntu is shown, with 20 Gb disk space. The settings can be changed by clicking on Customize Settings, now or later. For example, the amount of memory for Ubuntu can be set (choose 2 Gb or more), as well as the number of processors, and the amount of disk space.
Recall to run Update Manager in Ubuntu to update the operating system. You find the Update Manager under the menu System - Administration - Update Manager.
Multi-processor computers will normally let Ubuntu run on just one processor. The memory accessible from Ubuntu may also be (much) smaller than what the computer actually has available. At this time of writing it is unclear if a dual boot solution will give significantly more power to Ubuntu. The downside with a dual boot solution, compared to VMWare Fusion, is that the Ubuntu drivers might not be able to integrate all features of the track pad properly.
To modify the settings for processors and memory on the Ubuntu side, shut down the virtual machine by going to the VMWare Fusion menu panel og choosing Virtual Machine - Shut down. Then, in the same pull down menu, choose Settings and click on the menu item with Processors and Memory. Now the processors and memory can be adjusted to your needs for high-performance computing with Ubuntu.
Choosing too small memory (less than 1Gb) can make Ubuntu run slowly when you have a web browser with many windows for instance.
Keyboard. If your keyboard is Norwegian, you probably want to change from the default English/US keyboard in Ubuntu to Norwegian: System - Preferences - Keyboard - Layouts - Add ... - Norway. However, many prefer to do programming with an English/US keyboard and switch between this keyboard and the native language. Click on Options ... in the Layout window, choose Keys to switch keyboard layout by pressing a certain key combination, e.g., Ctrl-L + Shift-R toggles between English/US and Norwegian keyboards (very handy!).
You can find the Mac home folder under
on Ubuntu. Usually, you want to make a link with a more memorable name,
Linux> ln -s /mnt/hgfs $HOME/Mac-files
If you like to use the Places dropdown menu in Ubuntu for finding files, you can choose Computer, then File System, click mnt, and finally drag hgfs to the list of places in the left part of the window. Then you have easy access to your Mac files from the Places menu.
Copying text and files. Files can be copied or moved between the Mac and the Ubuntu machine. Text can also be copied. We refer to the VMWare documentation for more information.
Updating Ubuntu. See http://www.ivankristianto.com/os/ubuntu/things-you-want-to-do-after-install-ubuntu-10-04-desktop-part-2/1237/
When Ubuntu is up and going it is time to customize Ubuntu and install packages.
Internet Does not Work in Ubuntu. Invoke the VMWare Fusion menu Virtual Machine - Settings - Network and test Share the Mac's network connection versus Connect directly to the physical network (Bridged).
Go to Settings (Command-E) and turn off shared directories, then turn on (again) the desired shared directories.