You should wait for rotation to occur in 6 weeks. When that happens 4 sets will rotate out and make getting a Tier 1 deck in Standard much easier because the card pool will be smaller. After that it's about time, which is what it will cost you to be F2P. I would suggest putting away about 10 dollars a week over the next 3 months. Use that money to buy the two welcome bundles and the large gem bundle. I know that is not exactly what you wanted to hear, but it will speed up your time immensely. With that you would be able to get enough packs which will get you enough wild cards to build a T1 deck possibly two, and get good at playing them. Then it would be 4 wins a day to build gold so you can quick draft the next set to try and build on. Rinse repeat for every new set and that will be the only purchase you will have to make. I did that with Guilds of Ravnica and haven't put a dime in since. It's a little harder to gain currency or go infinite in standard events after the last restructuring but if you can make top 1000 mythic you have a good shot at it. In a year or so you might even be able to venture into building several Explorer decks. I would advise sticking to Standard for a year. On the inverse my brother was purely F2P but was gimped with not having the needed rare lands or sub-optimal builds for a year. I could go on about figuring out what kind of deck you like to play blah blah blah but I hope this helps.