Trying to lose weight, and trying to keep sugar levels down, but not enough to make me go hypo if I go for a walk

are you on a pump? If you are you can set a temp basal 2 hours before you go walking to stop the hypo. I walk 8 miles a day doing school runs and do an 70% basal from 6am to 9am. Insulin peaks at around 2 hours so I set it to start 2 hours before I go out. works a treat. 

If your MDI it would be a case of either eating carbs before you go or taking less insulin when you bolus for the meal before going. 

I am not on a pump

I try to keep to under 10 grams of carb when I eat in the day but eat a healthy meal at 6 pm ish usually fish new potatoes etc but never eat lots of carbs . Try to keep around 3  for what I eat. I've lost quite a bit of weight now so it works for me it may not be right for you ... a banana is good before I walk if I'm low ish say 7 but I don't work with low numbers like a lot of people so a low might be 5 for you. 5 for me means panick !! ( had a serious hypo in Feb so I'm on a libre sensor now ) been t1 for 8 years daily battle for me 

Thanks, I have been diabetic for longer, but as I am getting older, it is difficult, I have managed to walk, a few times, but usually I make sure it is on 10 then I do not need any extra, but went without bread at teatime the other day, it went to 5.8 during the evening, so had a small snack of cheese and cucumber, by the time the morning came round, it had gone up to 13, so going to try leaving out the snack in the evening, and maybe just having a glass of water of black tea