What does it mean to be "devoted to God"? Does it mean going to every church service and special event, and spending hours per day reading the Bible, praying, and worshiping? If you think that those things are signs of a person being devoted to Yahweh, you're wrong.
First, about the church services and special events. What are their purposes? If they are not to learn or do the will of God, then attending the event or service is a waste of time if your goal is to devote as much of your time as possible to Yahweh. And if the service or event does something that is contrary to the commands of Yahweh, then you must not attend such a service or event. Devotion in this case would be lovingly point-out that such an event or service is sinful.
What about reading the Bible, as you should be doing regularly? If this is not accompanied by putting what you read into practice, then you're just wasting your time. And what about prayer and worshiping? If your prayers and worship are done in a manner that Yahweh has forbidden, then you are wasting your time. In fact, if you refuse to put into practice what you have learned, even if you are not praying or worshiping in a manner that Yahweh has forbidden, then your prayer and worship are abominations (Proverbs 28:9)! Also, if your "devotion" in prayer, worship, or reading Scripture becomes a ritual, then you have completely lost sight of the purpose of such things!
All devotion to Yahweh starts with learning his commandments and putting them into practice. Abstaining from that which Yahweh has forbidden, and doing that which Yahweh has required. For anything that Yahweh has not forbidden or required, you have the freedom to choose to abstain from such things, or to partake of such things. After obedience comes motive. All things done as devotion to the Lord must be done to glorify God. For example: When you go to help those in need, do you help to be praised by those that see you helping? Or do you help out of love, and in the hope to be able to win them over to the Lord Yeshua? Only the latter is devotion to Yahweh.
The best form of obedience is the type that comes from the heart. In fact, this is what Yahweh meant when he said to love him with all our hearts. See Deuteronomy 6, 10, 11, 13, and 30 to see that this is the case. Yahweh doesn't want just obedience. He wants obedience from the heart. And this is what devotion to him starts with. It ends by going above and beyond what he requires of us. And that is not limited to simply praying, worshiping, reading the Bible, or going to all of the church services and special events. In fact, those things are minor in comparison to, for example, helping those who need help. Or if you are a teacher, devotion is teaching people how to live according to the will of Yahweh. And of course, all devotion is doing these things by the faith that we have in the Lord Yeshua, and not out of fear of Yahweh's judgement if you don't do these things.