Before you start you should familiarize yourself with the ARC Bios setup
and how to run programs from the ARC Bios screen.

You should also examine the guide on the OpenBSD/arc web site, which
will hopefully soon have more complete and more up-to-date instructions
than are given in the install document.

If you're installing OpenBSD/arc for the first time it's a very good idea
to look at the partition sizes of disk you intend installing OpenBSD on.
Changing the size of partitions after you've installed is difficult. If
you do not have a spare bootable disk, it may be simpler to re-install
OpenBSD again from scratch.

Asumming a classic partition scheme with root (`/') and /usr filesystems,
a comfortable size for the OpenBSD root filesystem partition (a) is about
32Mb. The install will take ~18Mb of that. Hovever it has shown that 60M
is not a bad choise when more packages are to be installed. It is recommended
that the 'a' partition and the MSDOS (i) partition uses the first 64Mb.
A good initial size for the swap (b) partition is twice the amount of physical
memory in your machine or at least 64M.
A minimum /usr partition (e) is ~150M but with that you will run into trouble
later. A minimum size of 350M is recommended. A full binary installation,
without X11 or any other additional software, takes about 120MB in `/usr'.