I am new to shooting with a scope. I just bought a Tikka T3 lite in 7mm-08 with a zeiss conquest I think its a 3.5 to 9 x 40mm. I plan on using it next week for a deer hunt expected range of shot to be 200 yards so I would like to zero at 200 yards shooting 140 gr federal boatail. I expect to hunt keeping the scope zoomed to 4.5 magnification. The scope supposedly has been boresighted by gunshop and factory rings lapped. What is the best way to sight this in?

go to the range.

make the groups center about 1.75" high at 100yards. this is assuming those 140s are doing around 2800fps with those factory federal vitalshocks. thats what i would do. even 2" high wouldnt harm

hate to sound stupid but should I keep the scope
at the magnification I will be hunting? Should I focus zoomed to 9x then back off to 4x, really don't know the basics of using the scope well enough to zero properly. I get the part about 2" high at 100 yrds and am aware I need to rest everything on a solid rest.

Shouldn't matter. I would suspect that for a shot at 200 yards, on a deer, you will need more than 4x. Use 9x, then after adjusting the scope to desired POI, you could, if you wanted to, back off to 4X and verify that the POI has not moved. On a scope like a Zeiss, I would be surprised if it did.
Peter.

I am taking it out tomorrow give it a go thanks. Yes I bought the zeiss expecting a good piece of gear.