"I'd like to learn a language, but don't really have the time." Does that statement sound at all familiar? If so then read on.
During a typical day, there are usually times when you could fit in a bit of language study. Even if you only study for five or ten minutes at a time, it all adds up in the end. In fact it can be beneficial to spread your studies over a number short periods, rather than doing it all in one or two big chunks. The more often you practice and review material, the better you'll remember it and be able to use it.
If you commute to work or school/college/university every day, perhaps you could use that time for study. Other times you could use for study/practice include while preparing meals, washing dishes, doing house work, gardening, jogging, queueing, during your lunch break or at the gym.
The type of study or practice will depend on what else you're doing. In some cases you could listen to a lesson or two, or to other material such as songs, audio books, radio programmes, etc. In others you could practice reading and/or writing in your L2, or even practice speaking. If you want to practice your speaking in a public, perhaps you could pretend to talk on your phone so that other people don't suspect your sanity and think you're talking to yourself.
While working, maybe you could listen to online radio stations and podcasts. Even if you don't listen to them very attentively, just having them burbling away in the background is benefical as it helps you to tune into the sounds and rhythms of your L2, and to pick up new words and phrases.
You can used physical or electronic flashcards to learn some vocabulary, grammar or other aspects of a language whenever you have a spare moment or two. If you make them yourself, you are more likely to remember what you're learning, as the process of making them can help the information stick in your memory.
You can find ways to make the language you're learning part of your everyday life by using it to do some of the things you normally do. For example, you could count repetitions when exercing in your L2. You could watch L2 versions of your favourite TV shows, if they are available. You could watch sports in your L2 - either coverage of games of the team(s) you support, and/or you could start following a team from a country where your L2 is spoken.
If you're interested in the food of the country or region where your L2 is spoken, you could learn some receipes through your L2 from books, websites or cooking shows. By doing so, you learn cooking and food vocabulary, and enjoy some tasty dishes.