I think the best thing to do is getting familiar with the language. It doesn't matter if you understand it or not, just start listening (and talking, if possible) Spanish. Movies, Youtube videos, Spanish speaking communities... Everything that makes this language an ussual thing in your life.
After that you will be able to start studing formal or informally, but it will be a "making sense of" something you already have in you.
I know this is not the common way to approach, but, at least for my, is the best way: start learning a language as something complety weird for you it's not something I'd recommend. It's a really easy way of getting frustrated.
One more thing: try to speak as much as you can. I doesn't really matters if you are making lots of mistakes. You should be able to speak from day one: if you wait until you're "perfect" or "good enough", you might never start speaking.
Well, the best thing is to figure out what you want to do with Spanish and start there. Do you want to be able to communicate at work or with relatives? Learn the specific vocabulary for it, get a textbook for grammar and practice. Practice speaking to yourself and record it with a phone and listen back to it, making adjustments to your accent. Keeping a daily journal also helps as it gives you reasons to look up tenses and new vocabulary which are relevant to you.
Try to make friends who speak Spanish fluently and will speak it with you so they can correct awkward wording and help you with pronunciation. There are a ton of apps for this, and they work like language exchanges.
Hope some of these tips help!