My pups are early on introduced to a place board by feeding them on one. It is a daily "fixture". When doing early OB they walk across one, sit on it and will begin remote "sit/here" off it. A great side benefit is repetitive "square facing" sits.
However, with an older dog (that is not imprinted early on), getting them comfortable (on and off) using OB and remote sits is the simplest. Once they "adjust" and if they can "handle" (take casts), the easiest way to transition to remote marking (where you stay in the field) is to "ladder" yourself away (throwing marks) and casting back from increasing distances. At first, you may have to walk the dog back and "help" him understand the routine. Making a game out of it and teaching is very effective. However, they need to be comfortable getting "on and off"........first.
The initial command from a distance is "place/back" (if they know what "back" means). The sooner you can transition to simply saying "place" (as a cast) the better. I think it is important for a dog to understand the difference in the "place" cast as opposed to "back" (for bllinds).
Now if the dog is not skilled in handling (young), it is still possible to teach the dog a routine where they will return on their own. I always use a place board when doing three handed casting. They learn quickly where they have to "go and be" to continue the drill.
The best approach is based on reading a dog's skill level and designing the proper teaching mode to achieve the desired expectation. It is my experience a "What's next?" dog that loves to train will catch on quickly at most any age.
"solo/remote line X-Box plus two marking drill (angled in/back & flat singles)"