Grocery shopping - something that is done by everybody, but not always done healthily. Nowadays there are two ways in which people do their weekly shop - in store and online. Both have their advantages and disadvantages.
I think that in store shopping is still the most popular, even though the online shop is consistently growing more popular. Shopping in store can be daunting to some, and many people 'go off track' when they enter the store. My first tip is to never go shopping when you are hungry, this can only lead to bad choices. If you are hungry and you decide to go food shopping, well.... your entering a massive store full of food, when you are craving food, not going to end well! So make sure you go shopping after you have eaten, this way you won't just be blind sighted by all the food available. My next tip is also something to do before you go grocery shopping - be prepared! Make sure you have a list before you leave for the weekly shop. By having a list, you know exactly what you are going to buy, so you don't end up walking up and down every single isle getting drawn in by all of the offers on unhealthy food.
You also want to stick to the 'outer isles', as the 'inner isles' tend to be where the unhealthy food is (not like that in every supermarket by the way...). The 'outer' areas tend to be where the fresh meat/fish counter is, vegetables and fruits.
Another tactic, that is also used to help save cash, is to give yourself a budget for each shop. This way, you cant just buy cakes, doughnuts and other fatty, sugary foods, as you won't have enough money to buy foods to actually have as meals for the week.
With online shopping, the above principles can come into play. If your hungry, and your on a supermarkets website, it is so easy and tempting to just click 'add to basket' on unhealthy foods. Obviously you don't have to worry about the isle problems with online shopping, but you do still get offers pop up everywhere, and it is very easy to just click on them. So, be careful, don't shop hungry, and stick to a list and budget!
I hope this helps you to have a healthier shop, and remember - eat clean to be lean!