New to open water

A couple of suggestions.  (Disclaimer: as I have no idea what kind of training you do just now I'm assuming that your background is "traditional" pool workouts based on a variety of sets and strokes.) You are training for an hour plus swim so you may want to increase the number of longer swims and longer sets that you do.  For example, you may want to do an hour for distance as one of your workouts once every two weeks.  Or use sets like 4x1000 descending to build endurance at pace over the longer distances.  You might like to try speed variation sets like a 2000 swum as 100 moderate working on efficiency and relaxation alternating with 100 hard/race pace+.  Are you racing skins rather than wetsuit? If so, I would not ignore kicking.  Lake swimming is in fresh water so you will not have the benefit wetsuit or salt water buoyancy.  Having well conditioned legs and a reasonable kick will help prevent them from becoming a drag and keeping a flat efficient body position.  (In a wetsuit you get body position "for free" as it were)  You can DM me if you have questions that I can help with.

Thanks so much! Yes, my background is only traditional indoor races/training. Not planning on wearing a wetsuit, so good to know not to get too wrapped up in focusing on pulling. 

Thanks so much! Yes, my background is only traditional indoor races/training. Not planning on wearing a wetsuit, so good to know not to get too wrapped up in focusing on pulling.