Well, I didn’t score very well in VR (630) so I may not be able to help, but I did get a 870 in AR.
First of all, are you using any resources? I woo pop ups seriously recommend the medify ucat crash course, although it is £45. I think there are longer courses too. It really trains you to work within the time limit
For VR, biggest tip is DONT PANIC. Panic might make you try to skim passages too fast. Bring fast is important, but getting the answer right is more important. I try to read the first paragraph of any passage in full so I at least have a good idea about what the passage is about. Any question about the author is likely to be in the last paragraph. If the passage is very complicated and sciency or too long - guess, flag, skip. There are no more marks for the difficult passages than the easy ones. UCAT is about being strategic, not perfect.
For AR, write down every pattern you see. Especially from the official ucat websites. You don’t have to memorise them - so long as you do enough questions you should become familiar. On the day of the exam, in the minute break before the AR, try writing down all the patterns you remember. Chances are they’ll repeat or be very similar. Lots of people say to use SCANS but I honestly found is too time-consuming. once you’ve done enough question, the overall arrangement of the shapes can be a big indicator of the rule. You can quickly rule out colour and number by looking at an overview. I think arrangement was the one that came up the most for me (e.g. the shape with the most sides on a specific edge can up twice)