Making Contact
It can happen to every secret naturist at some time or other. Despite all the skills they employ, be it going out after dark or in the small hours of the morning - one day they will have a close encounter, not with aliens which might not be a problem, but with people.
How the secret naturist reacts to any close encounter will depend on a number of factors, such as if you have been seen or not, if the person or persons show hostile reactions and so on. Perhaps, you have seen them but not they you, or you can hear people but they are still out of sight. Whatever the situation, it's difficult to suggest any set action because the circumstances of each encounter will differ and variables such as amount of time to react, distance between secret naturist and possible observer, etc, will also effect the response.
However, there are various suggested actions that the secret naturist can take before, during and after an encounter and the secret naturist should plan and rehearse a few scenarios in advance of the event occurring. If you have detected people but are yourself still unseen, if time allows and when carrying clothing, get dressed as quickly as possible. You can then continue until they are out of sight, then strip off again. If not carrying clothing, you should seek cover until they are passed. If no cover is available, you will just have to remain naked, smile and exchange pleasantries as you pass. Do not panic and run away, it gives the wrong impression.
If seen by an observer and if carrying clothing, slip on shorts to avoid offending the person and then apologise, saying you have been taken unawares and that you are a naturist. Again, as previously, if no clothing is available, you will just have to remain naked, smile and exchange pleasantries as you pass. It is best not to seek cover as this just arouses suspicion. In both the above cases, should the person become hostile, do not start to try and reason with them, they may become aggressive. In this case, I would strongly suggest you vacate the area immediately.
Explaining why you are naked can go some way towards maintaining good relations. The best, and in my opinion, the only answer to give, it that you are a naturist or nudist, who enjoys walking naked outdoors. Always act normally and openly, avoid behaving in a suspicious manner. If they see you as a simple eccentric, problems are less likely to occur.