Red triangles are fairly fragile. It’s easiest to land them if your triangle is very developed. Like, pulling it through until it starts getting small again, and then pull it through some more. At least for me. It would probably be wise to attempt a variety of formations.
As for suicides in general, practice multiple kinds. I find 1.5 to be easier than normal suicides. So, don’t be afraid to try to learn harder suicides. Also, string tension. Make sure it is perfect. Even a quarter twist of tension can mess you up. If your really having trouble with tension, a swivel might be a good idea. Another thing to work on is making sure of what the string on the other side of the yoyo is doing. Some people keep it tight, making there suicide loop big and fast. I keep it loose, resulting in a smaller, slower suicide. (If you have no idea what I’m talking about watch Yotrick’s then Yoyoexperts tutorial. See their different styles? That’s all I can think of right now… Oh, make sure your string is really, really visible. Like, neon yellow in the sun visible. Okay. Now that’s all I can think of. For now.