It's not hard to do. You can actually scour it in a washer provided that you can turn the agitation OFF. If not, you can scour it in a sink or tub, then spin it in the washer. Either way, washing it is the quick and easy part.
Combing and carding is the time consuming part. But there's a certain satisfaction that comes from finishing yarn that you started with raw fleece.
However, you can actually spin the wool straight from raw fleece, and wash the yarn afterwards... so long as the fleece has been skirted well and any large vegetive matter picked out. And so long as you can tolerate the smell of raw fleece.