Insemination Tips?

Does anyone have any tips for insemination? My wife and I use sterile cups and Frida fertility syringes. But I feel like every time we lose A LOT of the ejaculate. I tried putting my legs up and propping myself on pillows but I feel like it’s never any different. It almost immediately comes out. I thought about using a sterile speculum to open myself up to hopefully keep it all in as I feel like my cavity is small, if that’s even a thing. Would this be safe?