First Wet Specimen Questions

Hello! My roommate recently brought me home a dead immature magnolia warbler. It had just died outside and I put it right in the freezer. It’s been in there for 3 days. I really would like to wet specimen it! I have never done this before but I have the spirit and would love to do this right. How should I do everything?? Where do I buy it all??? Tips and tricks?? Thank you all!