The point of ramping up the clen dose is to assess side effects. If you know you handle it just fine, then jumping in at some point is fine. If not--and as this is your first time using it you don't know how you'll respond--then ramping up is the smart way to go. Clen's half life is over 24 hours, so if you go significantly higher than your body likes you might feel shitty for longer than a couple hours.
Clen will not stop all muscle loss. If you are not running an androgen cycle concurrently with your clen you can still lose lean tissue on drastic calorie deficits even though clen will aid in the muscle sparing efforts considerably.
In general, and as long as your schedule can handle it, I advise increasing your present calorie deficit through increasing activity from conditioning and such at first. This generally has a better "feel" without the deprivation associated with drastic calorie cutting and usually does not impact your recovery as badly because you have more fuel. This is particularly useful while ramping into your comfort zone on the dose. After you have figured out how your body reacts to your chosen top dose, you can start to cut calories more drastically and you will have a faster burning metabolism to do it with from the additional conditioning work you have been doing. In addition you won't feel as hungry as you would if drastically cutting calories right from the start.