The crosswind approach (in terms of doing pattern work) can be said to begin right from the moment the airplane leaves the ground and enter coordinated flight to maneuver through the traffic pattern for another landing. After takeoff and the airplane is flying coordinated, you will climb slightly off of runway heading adjusting (crabbing) for the crosswind to maintain runway centerline and inscribe the first part of your perfect rectangle in the traffic pattern. This may mean flying a heading a 240 or 245 when departing runway 23 with a right crosswind.
The next phase to think about is your crosswind leg. If making left traffic for a runway that is currently experiencing a right crosswind, you can anticipate having a strong tailwind on your crosswind leg. This would mean waiting a shorter amount of time before turning onto your downwind leg of the pattern so you do not get pushed too far from the runway.
Next is your downwind leg. Expect to fly with the nose pointed towards the runway when on a left downwind when there is a right crosswind blowing. I.e. downwind of runway 23 is 050, you may be flying 035 or 040. As you approach the point to begin your landing procedures (usually abeam your touchdown point) you will begin slowing down the airplane just before you deploy flaps. As you slow down the airplane, the wind will start to push you further sideways away from the runway (in the case mentioned above). To account for this, you will need to take a slightly larger “bite” or crab angle to maintain your pretty rectangle you are “drawing” on the ground (perhaps 030 instead of 035).
Now that we have our initial flaps set, have slowed down, and started our descent, we will continue to fly out from the runway, but not as far as usual since we are going to be flying a very “long” base leg (given a right crosswind for the runway and being a left base, we will have a large headwind as this point slowing down our ground speed considerably).