OK. Theoretically, this should be straightforward but you might need 10 mins or so.
Find that 'Settings' icon on the phone. It should be visible on the front screen. If not, shout. But you could just search on Google for something like 'how do I get the settings icon on an iPhone'. There will be multiple (easy) ways to get to it.
1. Name your phone.
Settings - General - About : You should see 'Name' right at the top. You may already have a name set. You can change it or if it's blank set a name of your choice, suggest something like 'DO's Iphone'
2. Set up personal hotspot
Go back to settings
The first 6 icons you might see stuff like Airplane Mode, WiFi (and if you're at home, it might show next to it that you're connected to your home broadband), Bluetooth, etc
You want the Personal Hotspot icon, tap on it
Now you will see two options - Allow Others to Join and WiFi Password
Click on WiFi Password
There will be a field with a cursor blinking. Enter whatever password you want here. Then click 'Done' up in the right-hand corner. It'll automatically go back to the previous screen. (This is different to all other passwords you might have on the phone, this is just for connecting your laptop to the phone and doesn't change other stuff like how you normally log in to the phone when you turn it on etc)
Now the Allow Others to Join will probably be showing off (white circle with grey to the right of it). Press the white circle and it should go green.
Put the phone down, go to the laptop.
3. Turning hotspot on on the laptop
If you're at home, you're probably connected to your own Broadband.
Look in the bottom right-hand corner, there should be a row of small icons.
One of them will be your broadband connectivity status icon (small dot bottom right with three curved lines emanating upwards to the left). If you hover the cursor over it, it tells you what you're currently connected to (will prob show your home broadband router name)
Click on that icon. There should be a list of all possible options you could connect to. Examples - your own router, maybe your next-door neighbours, a house across the street. This list is dynamic, it'll be different depending on where you are.
You probably know all this bit above anyway.
But now, you should also see 'DO's Iphone' as a option.
If you don't, get the phone, go to settings again, press on that Allow Others to Join button (to turn it off) and then immediately again to turn it green.
Now go back to that WiFi icon and click it again. Now you should see 'DO's Iphone' as an option. Click on it (you don't have to disconnect from whatever you're currently connected to) and click on the 'Connect' button.
If it's all worked, now you're using the phone's internet access on your laptop.
******
What could go wrong? Maybe your phone network provider doesn't allow it. Maybe you have to go ask them to enable hotspot functionality.
Notes:
- If you're in an area where the mobile phone signal is weak, then the internet connectivity might be flaky/slow (personally this rarely happens to me and is probably unlikely if you're in any built-up area)
- If someone calls you on the phone while you're using it as a hotspot, or you make a call, then it can drop the hotspot out. You go to do something on the laptop and nothing happens. In this case, you have to go back to the phone setting, turn off and back on again on the Allow Others to Join button. Then start again on the laptop WiFi connectivity, essentially repeating the process above.
- Using phone as hotspot seems (for me) to run down the phone battery quicker than you're usually used to. So if you're going to need a few hours and it's important, have a phone charger with you.
- If you take the phone more than about 10 feet away from the laptop, the hotspot may drop. Get the phone back closer to the laptop and start again.
- Whenever you want to start a new session of using the phone's internet, you have to go enable that Allow Others to Join button.
Something I'm not 100% sure about : Do you also need to have Bluetooth enabled in the phone settings? I don't think so. I believe this is entirely separate and is used for stuff like connecting your phone to your car sound system etc. But I could be wrong.
Something else : Do you need to have an iCloud account to make it work? I considered this a possibility. But my hotspot was working without me being logged in to my iCloud account. I concluded it's not relevant. But worth remembering as something to try if the process doesn't work.