I grew up with my parents speaking Gujarati. I was always able to understand but yet I always spoke in English and never learned how to speak. I can understand people very well, however I can barely put together sentences when speaking. I bought a colloquial course and a teach yourself, pretty much the only two good books on Gujarati. Should I still focus on reading and listening even though I can understand everything? My main problem is I just can’t recall the vocabulary when speaking.
Sounds mostly like an activation issue in that you just need practice. However, usually people who can understand well and read well can put out something halfway decent, even if they make a lot of mistakes or sound clumsy otherwise. For that reason, I would say don’t skip the input.
But maybe someone more experienced with this particular scenario can chime.
Also, for anyone else reading this thread, here’s what Google turned up:
Gujarati is an Indo-Aryan language native to the Indian state of Gujarat. It is part of the greater Indo-European language family. Gujarati is descended from Old Gujarati. Wikipedia
Native speakers: 50 million
Spoken by: Gujarati people
Language family: Indo-Aryan languages, Indo-European languages, Indo-Iranian languages, Gujarati languages
Writing system: Devanagari, Gujarati alphabet, Arabic script, Gujarati Braille
Native to: India
Region: Gujarat
Official language in: Gujarat, Dadra and Nagar Haveli, Daman and Diu
I think you need to find people who will speak to you in the language, so you get a chance to practise. You seem to have good listening skills in this language, it’s just the speech that’s missing. Being unable to recall vocabulary when speaking is fairly common I think. I assume it’s because you feel pressured and stressed? The brain tends to shut down under pressure, and it becomes harder and harder to retrieve words.
Probably best to try to get your parents to speak with you. They are likely to be very supportive, and won’t really care if you make mistakes. You can tell them beforehand that you can’t remember the words when speaking, so they just need to be patient.
It can also help if you first tackle using spoken Gujarati for basic communication e.g. what is the time, do you need help?, good morning, good evening, how are you?, how was your day?, I’m going to -insert place here- etc. If you keep doing these convos with your parents, that should build your confidence, as well as give you a chance to become used to forming the words too. It should also improve your memory a lot…because you’ll be speaking them repeatedly.
You can also have daily discussions with your parents, or any other friends/family who want to help you learn. Talk about subjects you are passionate about, as that tends to make you more motivated, which is always needed for language.
Go to Gujarati chat groups, teach others English in return for them speaking Gujarati with you.
But also, remember that just like reading, listening and writing…speaking in another language is also a process you build on slowly. It’s common and normal for students to be brilliant at one or more of these skills, but have trouble with one or more of them too. Try having small, structured speaking practice sessions. Just 10 minutes a day is enough in the first weeks, as it will be tiring for your brain to work the way you want it to. It’s a new skill, so give yourself time to learn how to do it, without putting pressure on yourself. I hope you achieve your dream of speaking Gujarati with a full command of your vocab/memory. 
Just speak whole the time. Quit the input. It’s not true having input making you able to output. You got the words that’s already something to have a decent start. Now talk and make exercises.
Speaking takes movement, you can play fifa whole day but one day you got to kick the ball yourself if you want to really play.