Hi Lewis
The basics you need are nicotine, pg and vg.
Now the important bit: recipes
I would advise thinking about the juices you like to vape, so tobacco or strawberry and creams or menthol ones or whatever, then if it's strawberry and cream then Google e liquid recipes strawberry and cream and check some out, arrange them by rating so you know your getting ones that have good feedback.
Once you have a couple you like the sound of, buy the flavourings for those and a few syringes and mix away.
Me personally, I would use darkstar vapes for it all as they have a decent stock of flavourings and all the other things you need.
If your serious and have the money I would advise you buy as much nicotine as you can in the next few days before TPD kicks in.
I'd you decide to use darkstar then use one of the below discount codes(try both and see which one works out cheapest)
Ds35tfa for 35% off tfa flavours
DSV11MA for 11% off everything
If you spend over 50 quid it's free shipping.
Hope that helps, you may want to let us know what kit you use to vape and we can advise you on pg/vg ratios and quantities to buy etc