Littlespace isn't some magical space where you "become" a child (mentally, emotionally). It also isn't "letting go".
In essence, Littlespace is a state of relaxation where a Little can more freely express themselves.
Entering Littlespace should be a natural occurrence to those who identify as Little. It isn't a very specific occurrence either — the setting doesn't have to be perfect to allow some degree of regression to be achieved. Bare in mind that regression is the amount of self-expression that one can comfortably carry out, and not how deeply one can fit into a role or a scene of a play.
We are not saying that there are not factors that impede this process, though. Growing up entails becoming aware of societal expectations and strapping on responsibilities to oneself and to those around us. With such come situations that require situational awareness and conformance. There can also be stressors, such as work being extra rough, not making ends meet, family emergencies.
Even so though, we believe that Littlespace isn't and shouldn't be out of reach. Because it isn't an on and off thing, and because one can't entirely shut out personality traits, it's always aaccessible in some form or another.
We think that the healthiest thing a Little can do when "having trouble entering Littlespace" is to rethink what regression is and to accept themselves. We say this because having personal unmet expectations can lead to grief and confusion, like "why can't I regress like any other Little?"
Now, a thing that helps most with relaxation is to recognize what situations you feel most relaxed being yourself in. If you're a social person, then allow yourself to be bright and bubbly with your friends. If you're a more quiet person, then set aside time to have privacy and comfort. Surround yourself with what makes YOU feel most comfortable and relax, and Regression should follow.