I would recommend buying or borrowing a lead sled. You do not want to develop a flinch while "learning" or becoming accustomed to the increased recoil.
I shoot a .340 weatherby and Have shot and handloaded this round for years. I do not use the sled all the time but when I start ramping up my shooting activities in the spring I use it.
Recoil that is generated from these mid bore magnums is serious stuff and can affect your shooting for a long time. Get a sled, use it until you feel like the gun is not going to hurt you and your confidence is up because you KNOW you will hit your target. Then start shooting from field positions to build your confidence. If you feel a flinch coming get back on the sled. eventually you will not need the sled.
I still use my sled often with sand bags especially when I am breaking in a new rifle or early season shooting some bigger stuff.
The up side is you have chosen a wonderful caliber. My hunting partner shoots a 338 win mag in fact I handload for him. He is very happy with it.
I would for sure bed the action and do the trigger work you will more than likely own this gun a long time.