Unless you are only wearing loafers indoors on white plush carpets, you don’t want a leather conditioner for your leather shoes, straps, or trim. Nor for your leather saddle. You want something that hydrates the leather, and keeps it from drying out, but you DON’T want to soften it. Normally our go to leather preservative is Brooks Proofide, and it works well. It’s also spendy and hard to find. A number of years ago, Rivendell Bicycle Works discovered Obenauf’s. I bought a can of it a decade ago, and was happy with the results. So now, here it is again. The can is bigger than the Brooks tin, so you could easily do 4 pairs of boots and all your saddles and have some left over for that questionable leather driving cap.
The messy but best way to apply leather goop: Start with a small amount. A pencil eraser head sized amount, and rub it in your hands to get it liquidy and hot. Then rub it in the saddle, getting all the edges and the top. Let it dry to a whitish film, then buff it off with one of those floor buffers that school building services guys use to murder small children with in horror movies. Wait, is there a movie where that happens? Probably not. If you happen to lack a huge floor buffer, you can use your roommate’s cleanest T shirt.
For the initial gooping of the underneath of the saddle, your roommates tooth brush is the preferred tool. Gets in all the crannies.
Made in the USA and all that.