Um ok I've never IV'd anything but I read on erowid a few things. It said use the smallest gauge needle possible to avoid blown veins.The bigger the number the smaller the bore/width of the needle. 21 is the one they usually use at the hozzy for taking a few veils of blood. They use a bigger one, around 19 gauge for large amounts of blood. I think for an injection you can use 28 gauge at the smallest. Use the least amount of water possible (0.5ml will be fine since I used a syringe to plug some dhc that I'd taken the needle off (obviously). It was 1.5ml, so 1/3 of that will be ok). If you're using pills try and use the smallest amount of pills possible ie 1 30mg pill instead of like 6 5mg pills to get the least possible binders. And always use micron filters before IVing pills. Where I live you can get them at pharmacies and needle exchanges. If it's a solution of morphine then don't worry about filtering obv.
You can inject in either your hand or your arm it's up to you I suppose if it were me I'd do my hand because you might find it easier/less fidgety and your hand veins stick out more than the one in the bend of your elbow, and if you fuck up and get an infectious abscess and you have to get it amputated, it'll be your hand, not your whole arm.
If you want I step by step guide it's probably somewhere on the internet but I guess being an anorexic I've had enough blood tests and when I was locked up in hospital getting my stomach working again they were giving me plenty of shit on IV for the abdominal pain so I'll try my best
Mr Keif Richards^ Please correct me if I'm wrong
You'll probably wanna invite a friend over incase something goes wrong and you start spraying blood
First, you should wash your hands. I don't think you have to be too thorough with washing your hands but use alcohol swabs/alcohol around the area you plan to shoot up
If you're gonna crush pills then filter them but you shouldn't heat it on a spoon or anything because then binders/filters that are insoluble in warm water and only become soluble when they're heated can solidify in your veins. Wouldn't be so terrible just once but if you're gonna make a habit of it then you might end up with necrosis or collapsed veins or whatever it is bagheads get. I used a shot glass when I was plugging to mix up the pills but it's up to you you could use a tea light case or whatever you want as long as it's clean. You can put a tiny piece of cotton in the liquid if you want, then draw up the solution through it for extra filtering. Don't use a cigarette filter because they contain glass which will fuck up your veins. You can use the plunger to mix it if you want, it made me feel cool so you might as well. If you're using tap water you could boil it to make it cleaner. Where I live they sell sterile water 2ml in boxes of ten. They also sell sachets of citric acid for base heroin if you ever find yourself going down that road.
If it's a solution of morphine then obv you can skip the crushing/mixing/filtering
It goes without saying that the needle should be clean. If you live in philly or jersey or something and can't get clean rigs from a drugstore/exchange, bleaching one would leave a thin layer of bleach residue on the inside of the syringe no matter how much you wash it (I've heard), but that's better than hepatitis I guess.
After you've drawn up the liquid into the syringe you're meant to rub your hands together to make them warmer and then push down on your arm where the vein is. It makes it easier to see apparently, idk why. If you're shooting up in your hand you prolly don't need to do that.
Tying something round your arm/wrist for some reason, again idk why but everyone does it.
Put the needle in flat as possible as not to go through the other side of the vein. In the same direction the vein travels, not across the side. You could go through the side that way.
Once the needle's in take off whatever you tied around your arm/wrist. Again, no clue why, but that's what the professionals do.
Pull back on the plunger. If you get a little blood, then nothing, you're not in a vein. If it's all blood then shoot away. About air, a tiny amount is fine but don't go shooting a 1/4 inch of the stuff. Try and get as little air in the syringe as you can. You can tap it so any air moves up to the top and you don't shoot it.
After checking you're in a vein, push the plunger down slowly so you don't blow a vein. If you're worried about oding then inject half, wait 20-30 seconds (with the needle still in your arm), then shoot the other half. I think that might only work with heroin because of the acetyl groups and crossing the blood brain barrier and all that, but I think if you overdosed by IV you'd know it pretty fast.
After that you're gonna wanna put a sterile cotton bud or something of that nature over the injection site and then pull the needle out. Leave it pressed there for a while till there's no blood. You can put a plaster on if you really wanna but I don't think it's necessary if you use the right gauge needle
I wouldn't do this till a mod or someone who actually has shot up has told me what a good job I did and commended me on my knowledge and my intellectual mind because I might be wrong
I hope I helped but I have no idea because of that vague ass title
Stay safe my dude ly