Just wondering if there are any good swimmers here (especially outdoor/distance swimmers) with good advice!
We have both signed up to do the Great North Swim in mid-June (1 mile, in Windermere). So far, swimming has been the ONLY sport which I am better at than DH - he is much fitter than me generally (runs, bikes, climbs, etc etc and can wipe the floor with me at any of those), but my swimming technique is better, thanks to swimming club in my schooldays, so I can usually beat him at that.
However... lately he has been getting into triathlons, so has been doing much more swimming training (and general exercise), and has improved quite a bit and already done several open-water swims, up to 1500m. Meanwhile, I have not been doing much swimming at all... and am not especially fit, nor used to open water. So I want to make sure he doesn't sneakily overtake 
I have already done 1 mile without stopping in the pool, so I know I can do the distance, although of course open water is a bit different. Also got a wetsuit sorted. But as I've not trained properly in a long time, I'm not really sure of the best way to improve my speed or prepare for it. I'm hoping to manage maybe 2 sessions a week, unlikely to fit in much more than that though.
I've had a look for training plans online and found lots of plans for getting up to 1 mile, but not much to help you do it faster. So thought I'd see if anyone here has any good tips as I will be slightly gutted if he beats me!
Thank you!