Sending companies messages like a CV almost is one way of asking. Its best to try with companies you really have an interest in or have used a lot
I was approached by my sponsor, I don’t hear of people asking for sponsorship very often..
companies generally approach riders. they usually go for riders with a larger social media following or those who have an evident rated horse show presence. i’m partnered with wellesley equestrian (use my code “weping10” for 10% off your entire purchase!!), katherine cosmetics, & sand cloud (use my code “ping25” for 25% off your entire order!!). good luck!!
I would start with an Instagram account, seeing as you can take videos, write captions, and interact with companies. Don’t have big expectations when you start out. Start with small brands and advertise them at shows! Then, other brand might want you as an ambassador.
Keep building up your social media outlets! Gets lotsbof followers and build great relationships with different companies by being a company ambassador! Then just keep connecting with different companies and you'll find some offers!