If you’ve only got five minutes a day to study Spanish, don’t expect to become fluent in a month or two. It’d be more realistic to say to yourself “I’d like to be able to understand basic Spanish in restaurants and shops, and be able to order my food in Spanish”.
Once you’ve reached that stage then you can re-assess your goals, and decide on your next mile-stone and time-frame. If you set yourself too big a goal at any stage, you’ll be disappointed with your progress.
So, what activities can we do which are most effective for people with little to no time?
With all this time that you’ve suddenly found, it’s not particularly practical to whip out a Spanish textbook and pen and start doing exercises while you’re waiting for the kettle to boil. We need appropriate, portable materials. Flashcards, small notebooks and phrasebooks, and a whole host of mobile apps (I’m not making any specific suggestions) can all be used in these gaps in the day. Try to find something which can be a complete exercise in the time you have available – a nugget of Spanish with which to intersperse your day.
Look at what you’re learning, and decide what is the most important. If something’s too boring or detailed for you right now, skip it and come back to it later. Unless an article you’re reading grabs you, read another one. You’ve only got a few minutes each day – spend it doing things which you enjoy and are beneficial, and you’ll find that you can retain a lot more. This will also help you to keep going.