These are not a fixed set of steps but a suggestion that can be changed according to what we are looking for.
For example:
Find out about the product specifications, reviews, etc. to learn about the products and choose the one that you think is best for you.
Use comparison sites to find the best prices and re-assess the product you are going to buy (when finding the best prices, sometimes you can find better products for less cost)
Check that you feel safe buying it and read any other information you might need. Consider the different type of delivery options.
You could also find the cheapest model of product you can and then assess if it could be enough for your needs.
Look at the "tips" section as there are suggestions that you can use when convenient.
Leave the product in the shopping trolley for few days before finalising the order (because of the cookies, companies might send you reminders with offers or vouchers)
Check product reviews critically
Check sellers reviews crtically
Check information about the product you want and similar products (wikipedia, blogs, forums, browser, youtube, etc.)
Check the product you are about to buy carefully, as sometimes the reviews are for similar products with different specifications ( in a laptop could be different battery capacity, different processor, ram memory, software included, etc.)
Reviews can be used carefully, as sometimes can be subjective and suspicious. They can help also to find out more information about the product.
Check the different possibilities of delivery (in my case I prefer to collect it in Doodle, if possible, to minimise risk).
Use incognito or private browsing: Epicbrowser.com, duckduckgo.com Google incognito, Firefox private browsing, Opera private window.
In Amazon, consider the pros/cons of different sellers.
Camelcamelcamel.com can be useful to learn the prices that Amazon has displayed on a product at different times
Sometimes the reviews are of similar products that are not exactly the same.
As a general rule you have 14 days to return a product you have ordered by mistake (or because you have found it cheaper). In the case of CD/DVD they cannot be opened (outer plastic film must be intact).
Use different browsers as the mentioned above and Internet Explorer so the cookies don't overload one browser only.
If your computer is slow, use opera as it demands less resources.
Consider different options such as buying, renting or borrowing.
Consider buying a model from the previous year rather than the latest and check the specifications and prices. Sometimes an old version has some feature that the latest one lacks.
using extensions to help online shopping, as different places might have different prices at different types for different customers. Recently I wanted to buy a very cheap product of £0.99 (free shipping). However, when in the basket I added 3 of them to buy, they added shipping costs that were far more costly than the product, however, I was able to buy them without shipping costs by buying each of them separately. As I said before, I would suggest searching for the top browser extensions for shopping online, such as alitools, camelcamelcamel (the camelizer), getinvisiblehand, etc. and also searching for their reviews.
When shopping online, make sure the website is a genuine one (safe with a padlock). Even if it is a genuine one, sometimes is good to print the screen to ensure that you are buying what you wanted (sometimes there are several tick boxes). You also can be saving or printing any message, confirmation, etc. even if it is just to remember exactly what the purchase was. If you buy something over the phone (something I try to avoid) make sure you send an email to confirm what has been agreed over the phone.
One of the things that made me to phone or contact the companies or search about it online, it is when I received emails on different occasions from a very famous shopping website and from the government... they seemed genuine!!!!!! However, as it was not normal that they would send me this type of emails I contacted them and searched for this type of scam online. This confirmed that the emails were not genuine, what was a relief because it seemed something that could be possible. Very worrying!!!!
If possible, I would advice to collect anything you buy, or collect it recorded delivery, to avoid possibilities of post missing. Sometimes I receive mail that is for other people, so I suppose the same could happen to others about my orders. On one occasion, somebody from a different building came to bring me a printer that had been delivered to him (I cannot understand how it happened).
Check that shops are not fake. Make sure you make pictures inside the phone (serial number,etc) as they can return something similar which is broken and ask for a refund. If you sell something and in ebay and says you are posting it, don't give it on hand (even if the buyer asks you), as the buyer could later say that you did not post it to him and you gave it to somebody else. When contacting a seller, use the contact forms from ebay or amazon, so that they keep the record in case you want later to complain.