No worries definitely understand being new on Ribblr! Here are some screenshots from the help center (using the keyword test) that will help with how to post a tester call, karma and testing guidelines to make sure your following the rules set by Ribblr 
click the text testing guidelines to be sent to the Ribblr post or click the link at the end, they both lead to the same place
Here’s some general info as well that I’ll do my best to explain, don’t hesitate to ask if you have other questions or need me to explain something further!
During testing phase Ribblr recommendeds creating a group chat with all the testers. You can start it by saying all the requirements you have and asking if the pattern is in their testing category. There testers will give your their feedback back/any mistakes/notes/etc about the pattern privately so you can fix/change the pattern as needed. The reason why this won’t be public like in a journal is that it’s public for everyone to view, so for instance if they see a lot of mistakes pointed out in a journal users would assume it’s still in the pattern and won’t get it, which is untrue as that was during the testing phase and not the final pattern. As long as the pattern is unpublished only the designer could see the journal. With that you would make sure there’s no information about the pattern explicitly written or shown (like step 1 MR…) as that would be public for all to see. Sometimes testers write out a specific part of the pattern to shlw you mistakes/ask for help at that area so that is only meant for ge private group tester message.
Journals are often asked by for designers to show credibility once the pattern is published but it’s up to you if you it’s required of testers. If it is mentioning if you want progress photos or just a final photo at the end of the finished product is up to you, but saying which you want/both is good so testers are aware of what they’re supposed to do.
In the screenshots above it mentions karma. Karma is giving to testers who complete tests one point per test. This can help show that they have done tests before and won’t ghost you. However new users or those that don’t test often will have little to no karma points so that’s important to keep in mind.
As the designer you give them karma points by clicking the gift and remove option for a tester. Only gift and remove if they completed the test this gives them the pattern and karm
I hoped this help explained some things, feel free to ask me to explain further on something, new questions, etc if you need an immediate answer feel free to use the help center (with or without a keyword) or using the search in the community with a keyword to see if any similar posts answered your question