Um well, if you've already done your stats test (Spearman's, Mann-Whitney or T-test) then you have to find a critical values table - if you search it on google they're fairly easy to find. You can then compare the outcome of your stats test with the numbers in the critical values table.
The headings in the table should be something like 0.1, 0.5, 0.01, 0.05, 0.001
For 5% confidence levels you need to be looking at the 0.5 column. I'm not sure about Mann-Whitney or the T-test but I used Spearman's and you literally just compare your value and if yours is a greater magnitude (so even if it is negative the number is greater) then you have a statistically significant result at the 5% level. So that means you can be 95% sure the correlation is significant - obviously then, in your coursework you'd talk about why that is.
If the result is significant at the other levels then even better!
Hope that helps and I hope I've got everything right
If I've said something that's not exactly right feel free to correct me