If I were you, I'd go heavier on the oxycodone and completely leave out the clonazepam. You have no tolerence to either drugs so it won't take too much to get desired effects. Try 25 mgs of oxycodone and then see where you are at.
This, it's not safe for beginners to be mixing CNS depressants, especially benzodiazepines with opioids, the risk of accidental overdose and fatal respiratory depression is so high, it's not worth risking. What you should do is just take more of your drug of choice, slowly titrating until you're at the level you want to be. Adding in benzodiazepines is a horrible idea, it's too dangerous for someone who isn't very tolerant to both classes of medications.
YMMV, everyone's body is different so what's safe for some, is incredibly dangerous for others. Don't mix opioids with benzodiazepines. If you're honestly considering doing it because people "do it all the time" then you should take a few steps back and look at how flawed your logic is. You know what people do all the time on this combination of drugs? Overdose and/or die.
You have next to no tolerance anyways, not tolerant to opioids, not tolerant to benzodiazepines. To be safe, abuse these medications separately, be mindful of their half-lives and mechanisms of actions.
TL;DR Chances are, if you have to make a thread about this online to ask, you don't have the tolerance to be considering this. And, if you have a speck of genius in you, you will find another safer way to enjoy yourself

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Some people regularly mix the two medications, as they have been directed to do so by their prescribing physicians, and the doctor there has weighed the benefits vs the consequences. It's still dangerous, accidents happen, and even taken as prescribed, bad things can happen if you aren't extra careful. These are incredibly potent CNS depressants, please respect them and treat them as such. They each synergize together very strongly, when combined the risks are exponential.