Upvote:4
The way to reapply is to file a new application from scratch.
In principle you can do that as soon as you have your passport back. There is no mandatory waiting period.
However -- as the refusal letters themselves point out -- if the reason why your first application was denied still applies when you apply again, you will just be refused again. That's a waste of money, and the more refusals you accumulate, the more suspicion will future applications be treated with,
So the meaningful time to apply again is not before your circumstances have changed such that you're not an illegal-immigration risk.